Cap analogs with 5'-terminal acyclic guanosine derivative

The compound according to any one of the preceding claims, wherein

• if n2 is 1, one of R3 and R4 is selected from the group consisting of C1-alkyl-O—RO, C1-alkyl-S—RS, C1-alkyl-S—S—RS, C1-alkyl-RP, O—Rc, RP, and 5- or 6-membered saturated, partially or fully unsaturated, or aromatic carbocyclyl, carbocyclyl-C1-C3-alkyl, heterocyclyl, or heterocyclyl-C1-C3-alkyl, wherein the aforementioned heterocyclic rings comprise one or more, same or different heteroatoms selected from O, N, or S, wherein said N- and/or S-atoms are independently oxidized or non-oxidized;
• and wherein each substitutable carbon or heteroatom in the aforementioned groups is independently unsubstituted or substituted with one or more, same or different substituents RX, wherein RX is halogen, CN, OH, SH, NH2, or C1-C4-alkyl;
• and the other one of R3 and R4 is H;
• if n5 is 1, one of R9 and R10 is selected from the group consisting of C1-alkyl-O—RO, C1-alkyl-S—RS, C1-alkyl-S—S—RS, C1-alkyl-RP, O—RO, RP, and 5- or 6-membered saturated, partially or fully unsaturated, or aromatic carbocyclyl, carbocyclyl-C1-C3-alkyl, heterocyclyl, or heterocyclyl-C1-C3-alkyl, wherein the aforementioned heterocyclic rings comprise one or more, same or different heteroatoms selected from O, N, or S, wherein said N- and/or S-atoms are independently oxidized or non-oxidized;
• and wherein each substitutable carbon or heteroatom in the aforementioned groups is independently unsubstituted or substituted with one or more, same or different substituents RX, wherein RX is halogen, CN, OH, SH, NH2, or C1-C4-alkyl;
• and the other one of R9 and R10 is H;
• and
• if n5 is 1, one of Re and Rf is selected from the group consisting of C1-alkyl-O—RO, C1-alkyl-S—RS, C1-alkyl-S—S—RS, C1-alkyl-RP, O—RO, RP, and 5- or 6-membered saturated, partially or fully unsaturated, or aromatic carbocyclyl, carbocyclyl-C1-C3-alkyl, heterocyclyl, or heterocyclyl-C1-C3-alkyl, wherein the aforementioned heterocyclic rings comprise one or more, same or different heteroatoms selected from O, N, or S, wherein said N- and/or S-atoms are independently oxidized or non-oxidized;
• and wherein each substitutable carbon or heteroatom in the aforementioned groups is independently unsubstituted or substituted with one or more, same or different substituents RX, wherein RX is halogen, CN, OH, SH, NH2, or C1-C4-alkyl;
• and the other one of R3 and R4 is H.

The compound according to any one of the preceding claims, wherein

• if n2 is 1, one of R3 and R4 is selected from the group consisting of C1-alkyl-O—RO, C1-alkyl-S—RS, C1-alkyl-S—S—RS, C1-alkyl-RP, O—RD, RP;
• and the other one of R3 and R4 is H;
• if n5 is 1, one of R9 and R10 is selected from the group consisting of C1-alkyl-O—RO, C1-alkyl-S—RS, C1-alkyl-S—S—RS, C1-alkyl-RP, O—RO, RP;
• and the other one of R9 and R10 is H;
• and
• if n8 is 1, one of Re and Rf is selected from the group consisting of C1-alkyl-O—RO, C1-alkyl-S—RS, C1-alkyl-S—S—RS, C1-alkyl-RP, O—RD, RP;
• and the other one of R3 and R4 is H.

The compound according to any one of the preceding claims, wherein

• RO, RS, RN1 and RN2, if present, are each independently selected from the group consisting of H, C1-C4-alkyl, and 5- or 6-membered saturated, partially or fully unsaturated, or aromatic carbocyclyl, carbocyclyl-C1-C2-alkyl, heterocyclyl, or heterocyclyl-C1-C2-alkyl, wherein the aforementioned heterocyclic rings comprise one or two, same or different heteroatoms selected from O, N, or S, wherein said N- and/or S-atoms are independently oxidized or non-oxidized;
• and wherein each substitutable carbon or heteroatom in the aforementioned groups is independently unsubstituted or substituted with one substituent RX, wherein RX is halogen, CN, OH, SH, NH2, or C1-C2-alkyl;
• and
• RD and RE, if present, are each independently selected from the group consisting of C1-C4-alkyl, and 5- or 6-membered saturated, partially or fully unsaturated, or aromatic carbocyclyl, carbocyclyl-C1-C2-alkyl, heterocyclyl, or heterocyclyl-C1-C2-alkyl, wherein the aforementioned heterocyclic rings comprise one or two, same or different heteroatoms selected from O, N, or S, wherein said N- and/or S-atoms are independently oxidized or non-oxidized;
• and wherein each substitutable carbon or heteroatom in the aforementioned groups is independently unsubstituted or substituted with one substituent RX, wherein RX is halogen, CN, OH, SH, NH2, or C1-C2-alkyl.

The compound according to any one of the preceding claims, wherein

• RO, RS, RN1 and RN2, if present, are each independently selected from the group consisting of H, C1-C3-alkyl, C1-C2-cyanoalkyl, and 6-membered saturated, partially or fully unsaturated, or aromatic carbocyclyl, carbocyclyl-C1-alkyl, heterocyclyl, or heterocyclyl-C1-alkyl, wherein the aforementioned heterocyclic rings comprise one or two heteroatoms selected from O, N, or S, wherein said N- and/or S-atoms are independently oxidized or non-oxidized;
• and wherein each substitutable carbon or heteroatom in the aforementioned groups is independently unsubstituted or substituted with one substituent RX, wherein RX is halogen;
• and
• RD and RE, if present, are each independently C1-C2-alkyl, preferably CH3.

A cap analog comprising a 5′ terminal acyclonucleoside, wherein the acyclonucleoside comprises a linear unbranched or linear single-branched structure instead of a ribose, wherein the cap analog is preferably a Cap1 analog or a Cap2 analog or a Cap2-1 analog, wherein the 5′ terminal acyclonucleoside is optionally deuterated, and wherein the linear unbranched or linear single-branched structure has the structure of formula (II):

• wherein
• n1 and n9 are independently selected from an integer ranging from 1 to 10;
• each of R1 and R2 is independently H, OH, SH, NH2 or halogen, wherein, if n1 is greater than 1, R1 may be same or different in each repeating unit, and R2 may be same or different in each repeating unit;
• each of R11 and R12 is independently H, OH, SH, NH2 or halogen, wherein, if n9 is greater than 1, R11 may be same or different in each repeating unit, and R12 may be same or different in each repeating unit;
• each of n3, n4, n6, and n7 is independently selected from an integer ranging from 0 to 5;
• wherein, if m is greater than 1, ne may be same or different in each repeating unit, and n7 may be same or different in each repeating unit;
• each of R5 and R6, if present, is independently H, OH, SH, NH2 or halogen, wherein, if n3 is greater than 1, R5 may be same or different in each repeating unit, and R5 may be same or different in each repeating unit;
• each of R7 and R8, if present, is independently H, OH, SH, NH2 or halogen, wherein, if n4 is greater than 1, R7 may be same or different in each repeating unit, and R8 may be same or different in each repeating unit;
• each of Ra and Rb, if present, is independently H, OH, SH, NH2 or halogen, wherein, if n6 is greater than 1, Ra may be same or different in each repeating unit, and Rb may be same or different in each repeating unit;
• each of Rc and Rd, if present, is independently H, OH, SH, NH2 or halogen, wherein, if n7 is greater than 1, Rc may be same or different in each repeating unit, and Rd may be same or different in each repeating unit;
• n2, n5 and n8 are independently selected from 0 or 1;
• wherein, if m is greater than 1, n8 may be same or different in each repeating unit;
• one of R3 and R4, if present, is selected from the group consisting of C1-C4-alkyl, C10C4-alkenyl, C10C4-alkinyl, C10C4-haloalkyl, C1-C3-alkyl-O—RO, C1-C3-alkyl-S—RS, C1-C3-alkyl-S—S—RS, C1-C3-alkyl-NRN1RN2, C1-C3-alkyl-RP, O—RD, S—RE, NRN3RN4, RP, and 3- to 10-membered saturated, partially or fully unsaturated, or aromatic carbocyclyl, carbocyclyl-C1-C3-alkyl, heterocyclyl, or heterocyclyl-C1-C3-alkyl, wherein the aforementioned heterocyclic rings comprise one or more, same or different heteroatoms selected from O, N, or S, wherein said N- and/or S-atoms are independently oxidized or non-oxidized;
• and wherein each substitutable carbon or heteroatom in the aforementioned groups is independently unsubstituted or substituted with one or more, same or different substituents RX, wherein RX is halogen, CN, OH, SH, NH2, C1-C4-alkyl, C1-C4-alkenyl, or C1-C4-alkinyl, or two RX attached to the same atom form an oxo group;
• and the other one of R3 and R4, if present, is selected from the group consisting of H, OH, SH, NH2 and halogen;
• one of R9 and R10, if present, is selected from the group consisting of C1-C4-alkyl, C1-C4-alkenyl, C1-C4-alkinyl, C1-C4-haloalkyl, C1-C3-alkyl-O—RO, C1-C3-alkyl-S—RS, C1-C3-alkyl-S—S—RS, C1-C3-alkyl-NRN1RN2, C1-C3-alkyl-RP, O—RD, S—RE, NRN3RN4, RP, and 3- to 10-membered saturated, partially or fully unsaturated, or aromatic carbocyclyl, carbocyclyl-C1-C3-alkyl, heterocyclyl, or heterocyclyl-C1-C3-alkyl, wherein the aforementioned heterocyclic rings comprise one or more, same or different heteroatoms selected from O, N, or S, wherein said N- and/or S-atoms are independently oxidized or non-oxidized;
• and wherein each substitutable carbon or heteroatom in the aforementioned groups is independently unsubstituted or substituted with one or more, same or different substituents RX, wherein RX is halogen, CN, OH, SH, NH2, C1-C4-alkyl, C1-C4-alkenyl, or C1-C4-alkinyl, or two RX attached to the same atom form an oxo group;
• and the other one of R9 and R10, if present, is selected from the group consisting of H, OH, SH, NH2 and halogen;
• one of Re and Rf, if present, is selected from the group consisting of C1-C4-alkyl, C1-C4-alkenyl, C1-C4-alkinyl, C1-C4-haloalkyl, C1-C3-alkyl-O—RO, C1-C3-alkyl-S—RS, C1-C3-alkyl-S—S—RS, C1-C3-alkyl-NRN1RN2, C1-C3-alkyl-RP, O—RD, S—RE, NRN3RN4, RP, and 3- to 10-membered saturated, partially or fully unsaturated, or aromatic carbocyclyl, carbocyclyl-C1-C3-alkyl, heterocyclyl, or heterocyclyl-C1-C3-alkyl, wherein the aforementioned heterocyclic rings comprise one or more, same or different heteroatoms selected from O, N, or S, wherein said N- and/or S-atoms are independently oxidized or non-oxidized;
• and wherein each substitutable carbon or heteroatom in the aforementioned groups is independently unsubstituted or substituted with one or more, same or different substituents RX, wherein RX is halogen, CN, OH, SH, NH2, C1-C4-alkyl, C1-C4-alkenyl, or C1-C4-alkinyl, or two RX attached to the same atom form an oxo group;
• and the other one of Re and Rf, if present, is selected from the group consisting of H, OH, SH, NH2 and halogen;
• m is selected from an integer ranging from 0 to 10, with the proviso that (i) if m is 0, one of n2 and n5 is 1 and the other one of n2 and n5 is 0, (ii) if m is 1, (a) n2, n5 and n8 are 0 or (b) one of n2, n5 and n8 is 1 and the other two of n2, n5 and n8 are 0;
• and (iii) if m is an integer ranging from 2 to 10, (a) n2, n5 and each no are 0, (b) one of n2 and n5 is 1 and the other one of n2 and n5 as well as each n8 are 0, or (c) one n8 is 1 and each other n8 as well as n2 and n5 are 0;
• L1 is selected from the group consisting of CH2, O, S, SO, SO2, NRL, CH(OH), CH(SH) and CH(halogen), with the proviso that, if m is 1 and n2, n5 and n8 are 0, L1 is selected from the group consisting of O, S, SO, SO2 and NRL;
• L2 is selected from the group consisting of O, S, SO, SO2 and NH;
• wherein, if m is greater than 1, L2 may be same or different in each repeating unit;
• RL is (i) H, if one of n2, n5 and n8 is 1, or (ii) selected from the group consisting of H, C1-C3-alkyl, C1-C3-alkyl-O—RO, C1-C3-alkyl-S—RS, C1-C3-alkyl-NRN1RN2, C1-C3-alkyl-RP and 3- to 10-membered saturated, partially or fully unsaturated, or aromatic carbocyclyl, carbocyclyl-C1-C3-alkyl, heterocyclyl, or heterocyclyl-C1-C3-alkyl, wherein the aforementioned heterocyclic rings comprise one or more, same or different heteroatoms selected from O, N, or S, wherein said N- and/or S-atoms are independently oxidized or non-oxidized, and wherein each substitutable carbon or heteroatom in the aforementioned groups is independently unsubstituted or substituted with one or more, same or different substituents RX, wherein RX is halogen, CN, OH, SH, NH2, or C1-C4-alkyl, or two RX attached to the same atom form an oxo group, if n2, n5 and n8 are 0,
• RO, RS, RN1 and RN2 are each independently selected from the group consisting of H, C1-C4-alkyl, C1-C4-alkenyl, C1-C4-alkinyl, C1-C4alkyl-O—C1-C4alkyl, C1-C4alkyl-O—C1-C4alkyl-O—C1-C4alkyl, C1-C4alkyl-O—C1-C4alkyl-O—C1-C4alkyl-O—C1-C4alkyl, C1-C4alkyl-S—C1-C4alkyl, C1-C4alkyl-S—C1-C4alkyl-S—C1-C4alkyl, C1-C4alkyl-S—C1-C4alkyl-S—C1-C4alkyl-S—C1-C4alkyl, C1-C4alkyl-NH—C1-C4alkyl, C1-C4alkyl-NH—C1-C4alkyl-NH—C1-C4alkyl, C1-C4alkyl-NH—C1-C4alkyl-NH—C1-C4alkyl-NH—C1-C4alkyl and 3- to 10-membered saturated, partially or fully unsaturated, or aromatic carbocyclyl, carbocyclyl-C1-C3-alkyl, heterocyclyl, or heterocyclyl-C1-C3-alkyl, wherein the aforementioned heterocyclic rings comprise one or more, same or different heteroatoms selected from O, N, or S, wherein said N- and/or S-atoms are independently oxidized or non-oxidized;
• and wherein each substitutable carbon or heteroatom in the aforementioned groups is independently unsubstituted or substituted with one or more, same or different substituents RX, wherein RX is halogen, CN, OH, SH, NH2, or C1-C4-alkyl, or two RX attached to the same atom form an oxo group;
• RD and RE are each independently selected from the group consisting of C1-C4-alkyl, C1-C4-alkenyl, C1-C4-alkinyl, C1-C4alkyl-O—C1-C4alkyl, C1-C4alkyl-O—C1-C4alkyl-O—C1-C4alkyl, C1-C4alkyl-O—C1-C4alkyl-O—C1-C4alkyl-O—C1-C4alkyl, C1-C4alkyl-S—C1-C4alkyl, C1-C4alkyl-S—C1-C4alkyl-S—C1-C4alkyl, C1-C4alkyl-S—C1-C4alkyl-S—C1-C4alkyl-S—C1-C4alkyl, C1-C4alkyl-NH—C1-C4alkyl, C1-C4alkyl-NH—C1-C4alkyl-NH—C1-C4alkyl, C1-C4alkyl-NH—C1-C4alkyl-NH—C1-C4alkyl-NH—C1-C4alkyl and 3- to 10-membered saturated, partially or fully unsaturated, or aromatic carbocyclyl, carbocyclyl-C1-C3-alkyl, heterocyclyl, or heterocyclyl-C1-C3-alkyl, wherein the aforementioned heterocyclic rings comprise one or more, same or different heteroatoms selected from O, N, or S, wherein said N- and/or S-atoms are independently oxidized or non-oxidized;
• and wherein each substitutable carbon or heteroatom in the aforementioned groups is independently unsubstituted or substituted with one or more, same or different substituents RX, wherein RX is halogen, CN, OH, SH, NH2, or C1-C4-alkyl, or two RX attached to the same atom form an oxo group;
• RN3 and RN4 are each independently selected from the group consisting of H, C1-C4-alkyl, C1-C4-alkenyl, C1-C4-alkinyl, C1-C4alkyl-O—C1-C4alkyl, C1-C4alkyl-O—C1-C4alkyl-O—C1-C4alkyl, C1-C4alkyl-O—C1-C4alkyl- O—C1-C4alkyl-O—C1-C4alkyl, C1-C4alkyl-S—C1-C4alkyl, C1-C4alkyl-S—C1-C4alkyl-S—C1-C4alkyl, C1-C4alkyl-S—C1-C4alkyl-S—C1-C4alkyl-S—C1-C4alkyl, C1-C4alkyl-NH—C1-C4alkyl, C1-C4alkyl-NH—C1-C4alkyl-NH—C1-C4alkyl, C1-C4alkyl-NH—C1-C4alkyl-NH—C1-C4alkyl-NH—C1-C4alkyl and 3- to 10-membered saturated, partially or fully unsaturated, or aromatic carbocyclyl, carbocyclyl-C1-C3-alkyl, heterocyclyl, or heterocyclyl-C1-C3-alkyl, wherein the aforementioned heterocyclic rings comprise one or more, same or different heteroatoms selected from O, N, or S, wherein said N- and/or S-atoms are independently oxidized or non-oxidized;
• and wherein each substitutable carbon or heteroatom in the aforementioned groups is independently unsubstituted or substituted with one or more, same or different substituents RX, wherein RX is halogen, CN, OH, SH, NH2, or C1-C4-alkyl, or two RX attached to the same atom form an oxo group, with the proviso that RN3 and RN4 are not both H;
• RP is
• , wherein
• X9 is O, S, NH or CH2;
• Y6 is O, S or Se;
• and
• each of Z6 and Z7 is independently OH, SH, SeH or BH3;
• and wherein the linear unbranched or linear single-branched structure is optionally deuterated.

An RNA molecule comprising at least three nucleotides and comprising a 5′ end of formula (III)

• wherein
• ring B1 is guanine, a modified guanine or a guanine analog;
• n1 and n9 are independently selected from an integer ranging from 1 to 10;
• each of R1 and R2 is independently H, OH, SH, NH2 or halogen, wherein, if n1 is greater than 1, R1 may be same or different in each repeating unit, and R2 may be same or different in each repeating unit;
• each of R11 and R12 is independently H, OH, SH, NH2 or halogen, wherein, if n9 is greater than 1, R11 may be same or different in each repeating unit, and R12 may be same or different in each repeating unit;
• each of n3, n4, n6, and n7 is independently selected from an integer ranging from 0 to 5;
• wherein, if m is greater than 1, n6 may be same or different in each repeating unit, and n7 may be same or different in each repeating unit;
• each of R5 and R6, if present, is independently H, OH, SH, NH2 or halogen, wherein, if n3 is greater than 1, R5 may be same or different in each repeating unit, and R6 may be same or different in each repeating unit;
• each of R7 and R8, if present, is independently H, OH, SH, NH2 or halogen, wherein, if n4 is greater than 1, R7 may be same or different in each repeating unit, and R8 may be same or different in each repeating unit;
• each of Ra and Rb, if present, is independently H, OH, SH, NH2 or halogen, wherein, if no is greater than 1, Ra may be same or different in each repeating unit, and Rb may be same or different in each repeating unit;
• each of Rc and Rd, if present, is independently H, OH, SH, NH2 or halogen, wherein, if n7 is greater than 1, Rc may be same or different in each repeating unit, and Rd may be same or different in each repeating unit;
• n2, n5 and n8 are independently selected from 0 or 1;
• wherein, if m is greater than 1, n8 may be same or different in each repeating unit;
• one of R3 and R4, if present, is selected from the group consisting of C1-C4-alkyl, C1-C4-alkenyl, C1-C4-alkinyl, C1-C4-haloalkyl, C1-C3-alkyl-O—RO, C1-C3-alkyl-S—RS, C1-C3-alkyl-S—S—RS, C1-C3-alkyl-NRN1RN2, C1-C3-alkyl-RP, O—RD, S—RE, NRN3RN4, RP, and 3- to 10-membered saturated, partially or fully unsaturated, or aromatic carbocyclyl, carbocyclyl-C1-C3-alkyl, heterocyclyl, or heterocyclyl-C1-C3-alkyl, wherein the aforementioned heterocyclic rings comprise one or more, same or different heteroatoms selected from O, N, or S, wherein said N- and/or S-atoms are independently oxidized or non-oxidized;
• and wherein each substitutable carbon or heteroatom in the aforementioned groups is independently unsubstituted or substituted with one or more, same or different substituents RX, wherein RX is halogen, CN, OH, SH, NH2, C1-C4-alkyl, C1-C4-alkenyl, or C1-C4-alkinyl, or two RX attached to the same atom form an oxo group;
• and the other one of R3 and R4, if present, is selected from the group consisting of H, OH, SH, NH2 and halogen;
• one of R9 and R10, if present, is selected from the group consisting of C1-C4-alkyl, C1-C4-alkenyl, C1-C4-alkinyl, C1-C4-haloalkyl, C1-C3-alkyl-O—RO, C1-C3-alkyl-S—RS, C1-C3-alkyl-S—S—RS, C1-C3-alkyl-NRN1RN2, C1-C3-alkyl-RP, O—RD, S—RE, NRN3RN4, RP, and 3- to 10-membered saturated, partially or fully unsaturated, or aromatic carbocyclyl, carbocyclyl-C1-C3-alkyl, heterocyclyl, or heterocyclyl-C1-C3-alkyl, wherein the aforementioned heterocyclic rings comprise one or more, same or different heteroatoms selected from O, N, or S, wherein said N- and/or S-atoms are independently oxidized or non-oxidized;
• and wherein each substitutable carbon or heteroatom in the aforementioned groups is independently unsubstituted or substituted with one or more, same or different substituents RX, wherein RX is halogen, CN, OH, SH, NH2, C1-C4-alkyl, C1-C4-alkenyl, or C1-C4-alkinyl, or two RX attached to the same atom form an oxo group;
• and the other one of R9 and R10, if present, is selected from the group consisting of H, OH, SH, NH2 and halogen;
• one of Re and Rf, if present, is selected from the group consisting of C1-C4-alkyl, C1-C4-alkenyl, C1-C4-alkinyl, C1-C4-haloalkyl, C1-C3-alkyl-O—RO, C1-C3-alkyl-S—RS, C1-C3-alkyl-S—S—RS, C1-C3-alkyl-NRN1RN2, C1-C3-alkyl-RP, O—RD, S—RE, NRN3RN4, RP, and 3- to 10-membered saturated, partially or fully unsaturated, or aromatic carbocyclyl, carbocyclyl-C1-C3-alkyl, heterocyclyl, or heterocyclyl-C1-C3-alkyl, wherein the aforementioned heterocyclic rings comprise one or more, same or different heteroatoms selected from O, N, or S, wherein said N- and/or S-atoms are independently oxidized or non-oxidized;
• and wherein each substitutable carbon or heteroatom in the aforementioned groups is independently unsubstituted or substituted with one or more, same or different substituents RX, wherein RX is halogen, CN, OH, SH, NH2, C1-C4-alkyl, C1-C4-alkenyl, or C1-C4-alkinyl, or two RX attached to the same atom form an oxo group;
• and the other one of Re and Rf, if present, is selected from the group consisting of H, OH, SH, NH2 and halogen;
• m is selected from an integer ranging from 0 to 10, with the proviso that (i) if m is 0, one of n2 and n5 is 1 and the other one of n2 and n5 is 0, (ii) if m is 1, (a) n2, n5 and n8 are 0 or (b) one of n2, n5 and n8 is 1 and the other two of n2, n5 and n8 are 0, and (iii) if m is an integer ranging from 2 to 10, (a) n2, n5 and each n8 are 0, (b) one of n2 and n5 is 1 and the other one of n2 and n5 as well as each n8 are 0, or (c) one n5 is 1 and each other n8 as well as n2 and n5 are 0;
• L1 is selected from the group consisting of CH2, O, S, SO, SO2, NRL, CH(OH), CH(SH) and CH(halogen), with the proviso that, if m is 1 and n2, n5 and n8 are 0, L1 is selected from the group consisting of O, S, SO, SO2 and NRL;
• L2 is selected from the group consisting of O, S, SO, SO2 and NH, wherein, if m is greater than 1, L2 may be same or different in each repeating unit;
• X1 is O, S, NH or CH2;
• RL is (i) H, if one of n2, n5 and n8 is 1, or (ii) selected from the group consisting of H, C1-C3-alkyl, C1-C3-alkyl-O—RO, C1-C3-alkyl-S—RS, C1-C3-alkyl-NRN1RN2, C1-C3-alkyl-RP and 3- to 10-membered saturated, partially or fully unsaturated, or aromatic carbocyclyl, carbocyclyl-C1-C3-alkyl, heterocyclyl, or heterocyclyl-C1-C3-alkyl, wherein the aforementioned heterocyclic rings comprise one or more, same or different heteroatoms selected from O, N, or S, wherein said N- and/or S-atoms are independently oxidized or non-oxidized, and wherein each substitutable carbon or heteroatom in the aforementioned groups is independently unsubstituted or substituted with one or more, same or different substituents RX, wherein RX is halogen, CN, OH, SH, NH2, or C1-C4-alkyl, or two RX attached to the same atom form an oxo group, if n2, n5 and n8 are 0;
• RO, RS, RN1 and RN2 are each independently selected from the group consisting of H, C1-C4-alkyl, C1-C4-alkenyl, C1-C4-alkinyl, C1-C4alkyl-O—C1-C4alkyl, C1-C4alkyl-O—C1-C4alkyl-O—C1-C4alkyl, C1-C4alkyl-O—C1-C4alkyl-O—C1-C4alkyl-O—C1-C4alkyl, C1-C4alkyl-S—C1-C4alkyl, C1-C4alkyl-S—C1-C4alkyl-S—C1-C4alkyl, C1-C4alkyl-S—C1-C4alkyl-S—C1-C4alkyl-S—C1-C4alkyl, C1-C4alkyl-NH—C1-C4alkyl, C1-C4alkyl-NH—C1-C4alkyl-NH—C1-C4alkyl, C1-C4alkyl-NH—C1-C4alkyl-NH—C1-C4alkyl-NH—C1-C4alkyl and 3- to 10-membered saturated, partially or fully unsaturated, or aromatic carbocyclyl, carbocyclyl-C1-C3-alkyl, heterocyclyl, or heterocyclyl-C1-C3-alkyl, wherein the aforementioned heterocyclic rings comprise one or more, same or different heteroatoms selected from O, N, or S, wherein said N- and/or S-atoms are independently oxidized or non-oxidized;
• and wherein each substitutable carbon or heteroatom in the aforementioned groups is independently unsubstituted or substituted with one or more, same or different substituents RX, wherein RX is halogen, CN, OH, SH, NH2, or C1-C4-alkyl, or two RX attached to the same atom form an oxo group;
• RD and RE are each independently selected from the group consisting of C1-C4-alkyl, C1-C4-alkenyl, C1-C4-alkinyl, C1-C4alkyl-O—C1-C4alkyl, C1-C4alkyl-O—C1-C4alkyl-O—C1-C4alkyl, C1-C4alkyl-O—C1-C4alkyl-O—C1-C4alkyl-O—C1-C4alkyl, C1-C4alkyl-S—C1-C4alkyl, C1-C4alkyl-S—C1-C4alkyl-S—C1-C4alkyl, C1-C4alkyl-S—C1-C4alkyl-S—C1-C4alkyl-S—C1-C4alkyl, C1-C4alkyl-NH—C1-C4alkyl, C1-C4alkyl-NH—C1-C4alkyl-NH—C1-C4alkyl, C1-C4alkyl-NH—C1-C4alkyl-NH—C1-C4alkyl-NH—C1-C4alkyl and 3- to 10-membered saturated, partially or fully unsaturated, or aromatic carbocyclyl, carbocyclyl-C1-C3-alkyl, heterocyclyl, or heterocyclyl-C1-C3-alkyl, wherein the aforementioned heterocyclic rings comprise one or more, same or different heteroatoms selected from O, N, or S, wherein said N- and/or S-atoms are independently oxidized or non-oxidized;
• and wherein each substitutable carbon or heteroatom in the aforementioned groups is independently unsubstituted or substituted with one or more, same or different substituents RX, wherein RX is halogen, CN, OH, SH, NH2, or C1-C4-alkyl, or two RX attached to the same atom form an oxo group;
• RN3 and RN4 are each independently selected from the group consisting of H, C1-C4-alkyl, C1-C4-alkenyl, C1-C4-alkinyl, C1-C4alkyl-O—C1-C4alkyl, C1-C4alkyl-O—C1-C4alkyl-O—C1-C4alkyl, C1-C4alkyl-O—C1-C4alkyl- O—C1-C4alkyl-O—C1-C4alkyl, C1-C4alkyl-S—C1-C4alkyl, C1-C4alkyl-S—C1-C4alkyl-S—C1-C4alkyl, C1-C4alkyl-S—C1-C4alkyl-S—C1-C4alkyl-S—C1-C4alkyl, C1-C4alkyl-NH—C1-C4alkyl, C1-C4alkyl-NH—C1-C4alkyl-NH—C1-C4alkyl, C1-C4alkyl-NH—C1-C4alkyl-NH—C1-C4alkyl-NH—C1-C4alkyl and 3- to 10-membered saturated, partially or fully unsaturated, or aromatic carbocyclyl, carbocyclyl-C1-C3-alkyl, heterocyclyl, or heterocyclyl-C1-C3-alkyl, wherein the aforementioned heterocyclic rings comprise one or more, same or different heteroatoms selected from O, N, or S, wherein said N- and/or S-atoms are independently oxidized or non-oxidized;
• and wherein each substitutable carbon or heteroatom in the aforementioned groups is independently unsubstituted or substituted with one or more, same or different substituents RX, wherein RX is halogen, CN, OH, SH, NH2, or C1-C4-alkyl, or two RX attached to the same atom form an oxo group, with the proviso that RN3 and RN4 are not both H;
• RP is
• wherein
• X9 is O, S, NH or CH2;
• Y6 is O, S or Se, and
• each of Z6 and Z7 is independently OH, SH, SeH or BH3;
• and wherein the 5′ end is optionally deuterated.

An RNA molecule comprising at least three nucleotides and comprising a 5′ terminal acyclonucleoside, wherein the acyclonucleoside comprises a linear unbranched or linear single-branched structure instead of a ribose, wherein the 5′ terminal acyclonucleoside is optionally deuterated, and wherein the linear unbranched or linear single-branched structure has the structure of formula (II):

• wherein
• n1 and ne are independently selected from an integer ranging from 1 to 10;
• each of R1 and R2 is independently H, OH, SH, NH2 or halogen, wherein, if n1 is greater than 1, R1 may be same or different in each repeating unit, and R2 may be same or different in each repeating unit;
• each of R11 and R12 is independently H, OH, SH, NH2 or halogen, wherein, if n6 is greater than 1, R11 may be same or different in each repeating unit, and R12 may be same or different in each repeating unit;
• each of n3, n4, n6, and n7 is independently selected from an integer ranging from 0 to 5;
• wherein, if m is greater than 1, n6 may be same or different in each repeating unit, and n7 may be same or different in each repeating unit;
• each of R5 and R6, if present, is independently H, OH, SH, NH2 or halogen, wherein, if n3 is greater than 1, R5 may be same or different in each repeating unit, and R5 may be same or different in each repeating unit;
• each of R7 and R8, if present, is independently H, OH, SH, NH2 or halogen, wherein, if n4 is greater than 1, R7 may be same or different in each repeating unit, and R8 may be same or different in each repeating unit;
• each of Ra and Rb, if present, is independently H, OH, SH, NH2 or halogen, wherein, if n6 is greater than 1, Ra may be same or different in each repeating unit, and Rb may be same or different in each repeating unit;
• each of Rc and Rd, if present, is independently H, OH, SH, NH2 or halogen, wherein, if n7 is greater than 1, Rc may be same or different in each repeating unit, and Rd may be same or different in each repeating unit;
• n2, n5 and n8 are independently selected from 0 or 1;
• wherein, if m is greater than 1, ne may be same or different in each repeating unit;
• one of R3 and R4, if present, is selected from the group consisting of C1-C4-alkyl, C10C4-alkenyl, C1-C4-alkinyl, C1-C4-haloalkyl, C1-C3-alkyl-O—RO, C1-C3-alkyl-S—RS, C1-C3-alkyl-S—S—RS, C1-C3-alkyl-NRN1RN2, C1-C3-alkyl-RP, O—RO, S—RE, NRN3RN4, RP, and 3- to 10-membered saturated, partially or fully unsaturated, or aromatic carbocyclyl, carbocyclyl-C1-C3-alkyl, heterocyclyl, or heterocyclyl-C1-C3-alkyl, wherein the aforementioned heterocyclic rings comprise one or more, same or different heteroatoms selected from O, N, or S, wherein said N- and/or S-atoms are independently oxidized or non-oxidized;
• and wherein each substitutable carbon or heteroatom in the aforementioned groups is independently unsubstituted or substituted with one or more, same or different substituents RX, wherein RX is halogen, CN, OH, SH, NH2, C1-C4-alkyl, C1-C4-alkenyl, or C1-C4-alkinyl, or two RX attached to the same atom form an oxo group;
• and the other one of R3 and R4, if present, is selected from the group consisting of H, OH, SH, NH2 and halogen;
• one of R9 and R10, if present, is selected from the group consisting of C1-C4-alkyl, C1-C4-alkenyl, C1-C4-alkinyl, C1-C4-haloalkyl, C1-C3-alkyl-O—RO, C1-C3-alkyl-S—RS, C1-C3-alkyl-S—S—RS, C1-C3-alkyl-NRN1RN2, C1-C3-alkyl-RP, O—RD, S—RE, NRN3RN4, RP, and 3- to 10-membered saturated, partially or fully unsaturated, or aromatic carbocyclyl, carbocyclyl-C1-C3-alkyl, heterocyclyl, or heterocyclyl-C1-C3-alkyl, wherein the aforementioned heterocyclic rings comprise one or more, same or different heteroatoms selected from O, N, or S, wherein said N- and/or S-atoms are independently oxidized or non-oxidized;
• and wherein each substitutable carbon or heteroatom in the aforementioned groups is independently unsubstituted or substituted with one or more, same or different substituents RX, wherein RX is halogen, CN, OH, SH, NH2, C1-C4-alkyl, C1-C4-alkenyl, or C1-C4-alkinyl, or two RX attached to the same atom form an oxo group;
• and the other one of R9 and R10, if present, is selected from the group consisting of H, OH, SH, NH2 and halogen;
• one of Re and Rf, if present, is selected from the group consisting of C1-C4-alkyl, C1-C4-alkenyl, C1-C4-alkinyl, C1-C4-haloalkyl, C1-C3-alkyl-O—RO, C1-C3-alkyl-S—RS, C1-C3-alkyl-S—S—RS, C1-C3-alkyl-NRN1RN2, C1-C3-alkyl-RP, O—RD, S—RE, NRN3RN4, RP, and 3- to 10-membered saturated, partially or fully unsaturated, or aromatic carbocyclyl, carbocyclyl-C1-C3-alkyl, heterocyclyl, or heterocyclyl-C1-C3-alkyl, wherein the aforementioned heterocyclic rings comprise one or more, same or different heteroatoms selected from O, N, or S, wherein said N- and/or S-atoms are independently oxidized or non-oxidized;
• and wherein each substitutable carbon or heteroatom in the aforementioned groups is independently unsubstituted or substituted with one or more, same or different substituents RX, wherein RX is halogen, CN, OH, SH, NH2, C1-C4-alkyl, C1-C4-alkenyl, or C1-C4-alkinyl, or two RX attached to the same atom form an oxo group;
• and the other one of Re and Rf, if present, is selected from the group consisting of H, OH, SH, NH2 and halogen;
• m is selected from an integer ranging from 0 to 10, with the proviso that (i) if m is 0, one of n2 and n5 is 1 and the other one of n2 and n5 is 0, (ii) if m is 1, (a) n2, n5 and n8 are 0 or (b) one of n2, n5 and n3 is 1 and the other two of n2, n5 and n8 are 0;
• and (iii) if m is an integer ranging from 2 to 10, (a) n2, n5 and each n8 are 0, (b) one of n2 and n5 is 1 and the other one of n2 and n5 as well as each n8 are 0, or (c) one n5 is 1 and each other n8 as well as n2 and n5 are 0;
• L1 is selected from the group consisting of CH2, O, S, SO, SO2, NRL, CH(OH), CH(SH) and CH(halogen), with the proviso that, if m is 1 and n2, n5 and n8 are 0, L1 is selected from the group consisting of O, S, SO, SO2 and NRL;
• L2 is selected from the group consisting of O, S, SO, SO2 and NH, wherein, if m is greater than 1, L2 may be same or different in each repeating unit;
• RL is (i) H, if one of n2, n5 and n8 is 1, or (ii) selected from the group consisting of H, C1-C3-alkyl, C1-C3-alkyl-O—RO, C1-C3-alkyl-S—RS, C1-C3-alkyl-NRN1N2, C1-C3-alkyl-RP and 3- to 10-membered saturated, partially or fully unsaturated, or aromatic carbocyclyl, carbocyclyl-C1-C3-alkyl, heterocyclyl, or heterocyclyl-C1-C3-alkyl, wherein the aforementioned heterocyclic rings comprise one or more, same or different heteroatoms selected from O, N, or S, wherein said N- and/or S-atoms are independently oxidized or non-oxidized, and wherein each substitutable carbon or heteroatom in the aforementioned groups is independently unsubstituted or substituted with one or more, same or different substituents RX, wherein RX is halogen, CN, OH, SH, NH2, or C1-C4-alkyl, or two RX attached to the same atom form an oxo group, if n2, n5 and n8 are 0;
• RO, RS, RN1 and RN2 are each independently selected from the group consisting of H, C1-C4-alkyl, C1-C4-alkenyl, C1-C4-alkinyl, C1-C4alkyl-O—C1-C4alkyl, C1-C4alkyl-O—C1-C4alkyl-O—C1-C4alkyl, C1-C4alkyl-O—C1-C4alkyl-O—C1-C4alkyl-O—C1-C4alkyl, C1-C4alkyl-S—C1-C4alkyl, C1-C4alkyl-S—C1-C4alkyl-S—C1-C4alkyl, C1-C4alkyl-S—C1-C4alkyl-S—C1-C4alkyl-S—C1-C4alkyl, C1-C4alkyl-NH—C1-C4alkyl, C1-C4alkyl-NH—C1-C4alkyl-NH—C1-C4alkyl, C1-C4alkyl-NH—C1-C4alkyl-NH—C1-C4alkyl-NH—C1-C4alkyl and 3- to 10-membered saturated, partially or fully unsaturated, or aromatic carbocyclyl, carbocyclyl-C1-C3-alkyl, heterocyclyl, or heterocyclyl-C1-C3-alkyl, wherein the aforementioned heterocyclic rings comprise one or more, same or different heteroatoms selected from O, N, or S, wherein said N- and/or S-atoms are independently oxidized or non-oxidized;
• and wherein each substitutable carbon or heteroatom in the aforementioned groups is independently unsubstituted or substituted with one or more, same or different substituents RX, wherein RX is halogen, CN, OH, SH, NH2, or C1-C4-alkyl, or two RX attached to the same atom form an oxo group;
• RD and RE are each independently selected from the group consisting of C1-C4-alkyl, C1-C4-alkenyl, C1-C4-alkinyl, C1-C4alkyl-O—C1-C4alkyl, C1-C4alkyl-O—C1-C4alkyl-O—C1-C4alkyl, C1-C4alkyl-O—C1-C4alkyl-O—C1-C4alkyl-O—C1-C4alkyl, C1-C4alkyl-S—C1-C4alkyl, C1-C4alkyl-S—C1-C4alkyl-S—C1-C4alkyl, C1-C4alkyl-S—C1-C4alkyl-S—C1-C4alkyl-S—C1-C4alkyl, C1-C4alkyl-NH—C1-C4alkyl, C1-C4alkyl-NH—C1-C4alkyl-NH—C1-C4alkyl, C1-C4alkyl-NH—C1-C4alkyl-NH—C1-C4alkyl-NH—C1-C4alkyl and 3- to 10-membered saturated, partially or fully unsaturated, or aromatic carbocyclyl, carbocyclyl-C1-C3-alkyl, heterocyclyl, or heterocyclyl-C1-C3-alkyl, wherein the aforementioned heterocyclic rings comprise one or more, same or different heteroatoms selected from O, N, or S, wherein said N- and/or S-atoms are independently oxidized or non-oxidized;
• and wherein each substitutable carbon or heteroatom in the aforementioned groups is independently unsubstituted or substituted with one or more, same or different substituents RX, wherein RX is halogen, CN, OH, SH, NH2, or C1-C4-alkyl, or two RX attached to the same atom form an oxo group;
• RN3 and RN4 are each independently selected from the group consisting of H, C1-C4-alkyl, C1-C4-alkenyl, C1-C4-alkinyl, C1-C4alkyl-O—C1-C4alkyl, C1-C4alkyl-O—C1-C4alkyl-O—C1-C4alkyl, C1-C4alkyl-O—C1-C4alkyl- O—C1-C4alkyl-O—C1-C4alkyl, C1-C4alkyl-S—C1-C4alkyl, C1-C4alkyl-S—C1-C4alkyl-S—C1-C4alkyl, C1-C4alkyl-S—C1-C4alkyl-S—C1-C4alkyl-S—C1-C4alkyl, C1-C4alkyl-NH—C1-C4alkyl, C1-C4alkyl-NH—C1-C4alkyl-NH—C1-C4alkyl, C1-C4alkyl-NH—C1-C4alkyl-NH—C1-C4alkyl-NH—C1-C4alkyl and 3- to 10-membered saturated, partially or fully unsaturated, or aromatic carbocyclyl, carbocyclyl-C1-C3-alkyl, heterocyclyl, or heterocyclyl-C1-C3-alkyl, wherein the aforementioned heterocyclic rings comprise one or more, same or different heteroatoms selected from O, N, or S, wherein said N- and/or S-atoms are independently oxidized or non-oxidized;
• and wherein each substitutable carbon or heteroatom in the aforementioned groups is independently unsubstituted or substituted with one or more, same or different substituents RX, wherein RX is halogen, CN, OH, SH, NH2, or C1-C4-alkyl, or two RX attached to the same atom form an oxo group, with the proviso that RN3 and RN4 are not both H;
• RP is
• wherein
• X9 is O, S, NH or CH2;
• Y6 is O, S or Se;
• and
• each of Z6 and Z7 is independently OH, SH, SeH or BH3;
• and wherein the linear unbranched or linear single-branched structure is optionally deuterated.

A process for preparing a compound of formula (I):

• or a salt, stereoisomer, tautomer, or deuterated version thereof, wherein
• R13 is
• wherein
• R15 is OH or
• ring B1 is guanine, a modified guanine or a guanine analog;
• n1 and n9 are independently selected from an integer ranging from 1 to 10;
• each of R1 and R2 is independently H, OH, SH, NH2 or halogen, wherein, if n1 is greater than 1, R1 may be same or different in each repeating unit, and R2 may be same or different in each repeating unit;
• each of R11 and R12 is independently H, OH, SH, NH2 or halogen, wherein, if n9 is greater than 1, R11 may be same or different in each repeating unit, and R12 may be same or different in each repeating unit;
• each of n3, n4, n6, and n7 is independently selected from an integer ranging from 0 to 5;
• wherein, if m is greater than 1, n6 may be same or different in each repeating unit, and n7 may be same or different in each repeating unit;
• each of R5 and R6, if present, is independently H, OH, SH, NH2 or halogen, wherein, if n3 is greater than 1, R5 may be same or different in each repeating unit, and R6 may be same or different in each repeating unit;
• each of R7 and Ra, if present, is independently H, OH, SH, NH2 or halogen, wherein, if n4 is greater than 1, R7 may be same or different in each repeating unit, and Ra may be same or different in each repeating unit;
• each of Ra and Rb, if present, is independently H, OH, SH, NH2 or halogen, wherein, if n6 is greater than 1, Ra may be same or different in each repeating unit, and Rb may be same or different in each repeating unit;
• each of Rc and Rd, if present, is independently H, OH, SH, NH2 or halogen, wherein, if n7 is greater than 1, Rd may be same or different in each repeating unit, and Rd may be same or different in each repeating unit;
• n2, n5 and n8 are independently selected from 0 or 1;
• wherein, if m is greater than 1, n8 may be same or different in each repeating unit;
• one of R3 and R4, if present, is selected from the group consisting of C1-C4-alkyl, C1-C4-alkenyl, C1-C4-alkinyl, C1-C4-haloalkyl, C1-C3-alkyl-O—RO, C1-C3-alkyl-S—RS, C1-C3-alkyl-S—S—RS, C1-C3-alkyl-NRN1RN2, C1-C3-alkyl-RP, O—RD, S—RE, NRN3RN4, RP, and 3- to 10-membered saturated, partially or fully unsaturated, or aromatic carbocyclyl, carbocyclyl-C1-C3-alkyl, heterocyclyl, or heterocyclyl-C1-C3-alkyl, wherein the aforementioned heterocyclic rings comprise one or more, same or different heteroatoms selected from O, N, or S, wherein said N- and/or S-atoms are independently oxidized or non-oxidized;
• and wherein each substitutable carbon or heteroatom in the aforementioned groups is independently unsubstituted or substituted with one or more, same or different substituents RX, wherein RX is halogen, CN, OH, SH, NH2, C1-C4-alkyl, C1-C4-alkenyl, or C1-C4-alkinyl, or two RX attached to the same atom form an oxo group;
• and the other one of R3 and R4, if present, is selected from the group consisting of H, OH, SH, NH2 and halogen;
• one of R9 and R10, if present, is selected from the group consisting of C1-C4-alkyl, C1-C4-alkenyl, C1-C4-alkinyl, C1-C4-haloalkyl, C1-C3-alkyl-O—RO, C1-C3-alkyl-S—RS, C1-C3-alkyl-S—S—RS, C1-C3-alkyl-NRN1RN2, C1-C3-alkyl-RP, O—RD, S—RE, NRN3RN4, RP, and 3- to 10-membered saturated, partially or fully unsaturated, or aromatic carbocyclyl, carbocyclyl-C1-C3-alkyl, heterocyclyl, or heterocyclyl-C1-C3-alkyl, wherein the aforementioned heterocyclic rings comprise one or more, same or different heteroatoms selected from O, N, or S, wherein said N- and/or S-atoms are independently oxidized or non-oxidized;
• and wherein each substitutable carbon or heteroatom in the aforementioned groups is independently unsubstituted or substituted with one or more, same or different substituents RX, wherein RX is halogen, CN, OH, SH, NH2, C1-C4-alkyl, C1-C4-alkenyl, or C1-C4-alkinyl, or two RX attached to the same atom form an oxo group;
• and the other one of R9 and R10, if present, is selected from the group consisting of H, OH, SH, NH2 and halogen;
• one of Re and Rf, if present, is selected from the group consisting of C1-C4-alkyl, C1-C4-alkenyl, C1-C4-alkinyl, C1-C4-haloalkyl, C1-C3-alkyl-O—RO, C1-C3-alkyl-S—RS, C1-C3-alkyl-S—S—RS, C1-C3-alkyl-NRN1RN2, C1-C3-alkyl-RP, O—RD, S—RE, NRN3RN4, RP, and 3- to 10-membered saturated, partially or fully unsaturated, or aromatic carbocyclyl, carbocyclyl-C1-C3-alkyl, heterocyclyl, or heterocyclyl-C1-C3-alkyl, wherein the aforementioned heterocyclic rings comprise one or more, same or different heteroatoms selected from O, N, or S, wherein said N- and/or S-atoms are independently oxidized or non-oxidized;
• and wherein each substitutable carbon or heteroatom in the aforementioned groups is independently unsubstituted or substituted with one or more, same or different substituents RX, wherein RX is halogen, CN, OH, SH, NH2, C1-C4-alkyl, C1-C4-alkenyl, or C1-C4-alkinyl, or two RX attached to the same atom form an oxo group;
• and the other one of Re and Rf, if present, is selected from the group consisting of H, OH, SH, NH2 and halogen;
• m is selected from an integer ranging from 0 to 10, with the proviso that (i) if m is 0, one of n2 and n5 is 1 and the other one of n2 and n5 is 0, (ii) if m is 1, (a) n2, n5 and n8 are 0 or (b) one of n2, n5 and n8 is 1 and the other two of n2, n5 and n8 are 0, and (iii) if m is an integer ranging from 2 to 10, (a) n2, n5 and each n8 are 0, (b) one of n2 and n5 is 1 and the other one of n2 and n5 as well as each n8 are 0, or (c) one n5 is 1 and each other n8 as well as n2 and n5 are 0;
• n10 is selected from 0, 1 or 2;
• L1 is selected from the group consisting of CH2, O, S, SO, SO2, NRL, CH(OH), CH(SH) and CH(halogen), with the proviso that, if m is 1 and n2, n5 and n8 are 0, L1 is selected from the group consisting of O, S, SO, SO2 and NRL;
• L2 is selected from the group consisting of O, S, SO, SO2 and NH;
• wherein, if m is greater than 1, L2 may be same or different in each repeating unit;
• each of X1 through X3 is independently O, S, NH or CH2, wherein, if n10 is 2, X3 may be same or different in each repeating unit;
• each of Y1 through Y5 is independently 0, S or Se, wherein, if n10 is 2, Y2 may be same or different in each repeating unit;
• each of Z1 through Z5 is independently OH, SH, SeH or BH3, wherein, if n10 is 2, Z2 may be same or different in each repeating unit;
• R14 is (i) selected from the group consisting of H, OH, OC1-C3-alkyl, and Opropargyl, wherein the dashed methylene bridge between R14 and the 4′ C is absent, or (ii) O, wherein the dashed methylene bridge between R14 being O and the 4′ C is present;
• R16 is (i) selected from the group consisting of H, OH, OC1-C3-alkyl, and Opropargyl, wherein the dashed methylene bridge between R16 and the 4′ C is absent, or (ii) O, wherein the dashed methylene bridge between R16 being O and the 4′ C is present;
• RL is (i) H, if one of n2, n5 and n8 is 1, or (ii) selected from the group consisting of H, C1-C3-alkyl, C1-C3-alkyl-O—RO, C1-C3-alkyl-S—RS, C1-C3-alkyl-NRN1RN2, C1-C3-alkyl-RP and 3- to 10-membered saturated, partially or fully unsaturated, or aromatic carbocyclyl, carbocyclyl-C1-C3-alkyl, heterocyclyl, or heterocyclyl-C1-C3-alkyl, wherein the aforementioned heterocyclic rings comprise one or more, same or different heteroatoms selected from O, N, or S, wherein said N- and/or S-atoms are independently oxidized or non-oxidized, and wherein each substitutable carbon or heteroatom in the aforementioned groups is independently unsubstituted or substituted with one or more, same or different substituents RX, wherein RX is halogen, CN, OH, SH, NH2, or C1-C4-alkyl, or two RX attached to the same atom form an oxo group, if n2, n5 and n8 are 0;
• RO, RS, RN1 and RN2 are each independently selected from the group consisting of H, C1-C4-alkyl, C1-C4-alkenyl, C1-C4-alkinyl, C1-C4alkyl-O—C1-C4alkyl, C1-C4alkyl-O—C1-C4alkyl-O—C1-C4alkyl, C1-C4alkyl-O—C1-C4alkyl-O—C1-C4alkyl-O—C1-C4alkyl, C1-C4alkyl-S—C1-C4alkyl, C1-C4alkyl-S—C1-C4alkyl-S—C1-C4alkyl, C1-C4alkyl-S—C1-C4alkyl-S—C1-C4alkyl-S—C1-C4alkyl, C1-C4alkyl-NH—C1-C4alkyl, C1-C4alkyl-NH—C1-C4alkyl-NH—C1-C4alkyl, C1-C4alkyl-NH—C1-C4alkyl-NH—C1-C4alkyl-NH—C1-C4alkyl and 3- to 10-membered saturated, partially or fully unsaturated, or aromatic carbocyclyl, carbocyclyl-C1-C3-alkyl, heterocyclyl, or heterocyclyl-C1-C3-alkyl, wherein the aforementioned heterocyclic rings comprise one or more, same or different heteroatoms selected from O, N, or S, wherein said N- and/or S-atoms are independently oxidized or non-oxidized;
• and wherein each substitutable carbon or heteroatom in the aforementioned groups is independently unsubstituted or substituted with one or more, same or different substituents RX, wherein RX is halogen, CN, OH, SH, NH2, or C1-C4-alkyl, or two RX attached to the same atom form an oxo group;
• RD and RE are each independently selected from the group consisting of C1-C4-alkyl, C1-C4-alkenyl, C1-C4-alkinyl, C1-C4alkyl-O—C1-C4alkyl, C1-C4alkyl-O—C1-C4alkyl-O—C1-C4alkyl, C1-C4alkyl-O—C1-C4alkyl-O—C1-C4alkyl-O—C1-C4alkyl, C1-C4alkyl-S—C1-C4alkyl, C1-C4alkyl-S—C1-C4alkyl-S—C1-C4alkyl, C1-C4alkyl-S—C1-C4alkyl-S—C1-C4alkyl-S—C1-C4alkyl, C1-C4alkyl-NH—C1-C4alkyl, C1-C4alkyl-NH—C1-C4alkyl-NH—C1-C4alkyl, C1-C4alkyl-NH—C1-C4alkyl-NH—C1-C4alkyl-NH—C1-C4alkyl and 3- to 10-membered saturated, partially or fully unsaturated, or aromatic carbocyclyl, carbocyclyl-C1-C3-alkyl, heterocyclyl, or heterocyclyl-C1-C3-alkyl, wherein the aforementioned heterocyclic rings comprise one or more, same or different heteroatoms selected from O, N, or S, wherein said N- and/or S-atoms are independently oxidized or non-oxidized;
• and wherein each substitutable carbon or heteroatom in the aforementioned groups is independently unsubstituted or substituted with one or more, same or different substituents RX, wherein RX is halogen, CN, OH, SH, NH2, or C1-C4-alkyl, or two RX attached to the same atom form an oxo group;
• RN3 and RN4 are each independently selected from the group consisting of H, C1-C4-alkyl, C1-C4-alkenyl, C1-C4-alkinyl, C1-C4alkyl-O—C1-C4alkyl, C1-C4alkyl-O—C1-C4alkyl-O—C1-C4alkyl, C1-C4alkyl-O—C1-C4alkyl- O—C1-C4alkyl-O—C1-C4alkyl, C1-C4alkyl-S—C1-C4alkyl, C1-C4alkyl-S—C1-C4alkyl-S—C1-C4alkyl, C1-C4alkyl-S—C1-C4alkyl-S—C1-C4alkyl-S—C1-C4alkyl, C1-C4alkyl-NH—C1-C4alkyl, C1-C4alkyl-NH—C1-C4alkyl-NH—C1-C4alkyl, C1-C4alkyl-NH—C1-C4alkyl-NH—C1-C4alkyl-NH—C1-C4alkyl and 3- to 10-membered saturated, partially or fully unsaturated, or aromatic carbocyclyl, carbocyclyl-C1-C3-alkyl, heterocyclyl, or heterocyclyl-C1-C3-alkyl, wherein the aforementioned heterocyclic rings comprise one or more, same or different heteroatoms selected from O, N, or S, wherein said N- and/or S-atoms are independently oxidized or non-oxidized;
• and wherein each substitutable carbon or heteroatom in the aforementioned groups is independently unsubstituted or substituted with one or more, same or different substituents RX, wherein RX is halogen, CN, OH, SH, NH2, or C1-C4-alkyl, or two RX attached to the same atom form an oxo group, with the proviso that RN3 and RN4 are not both H,
• RP is
• wherein
• X9 is O, S, NH or CH2;
• Y6 is O, S or Se, and
• each of Z6 and Z7 is independently OH, SH, SeH or BH3;
• and
• each of ring B2 through ring B4 is independently a nucleobase, a modified nucleobase or a nucleobase analog;
• wherein the process comprises
• reacting a compound of formula (IV)
• wherein B1, R1, R2, R3, R4, R5, R6, R7, R8, R9, R10, R11, R12, Ra, Rb, Rc, Rd, Re, Rf, n1, n2, n3, n4, n5, n6, n7, n8, n9, m, L1, L2, X1, Y1, Z1 are as defined above for formula (I),
• with a compound of formula (V)
• wherein X2, Y2, Z2, X3, Y3, Z3, X4, Y4, Z4, X5, X6, R14, R15, R16, B2, and B3 are as defined above for formula (I).