Anhydro sugar derivatives of indolocarbazoles

A compound according to the formula:

• or a stereoisomer or pharmaceutically acceptable salt or solvate thereof, useful for inhibiting topoisomerase I and the proliferation of tumor cells, wherein:
• R is hydrogen, OH, OC1-7alkyl, NH2, N(C1-3alkyl)2 or C1-7alkyl, wherein said C1-7alkyl is optionally substituted with one or more substituents selected from the group consisting of halogen, CN, OR9 and NR9R10;
• Q is O, S, CH2 or NR5a;
• R and R5a are each independently selected from the group consisting of:
• hydrogen, Formula (B), Formula (C), and Formula (D):
• provided that:
• if Q is NR5a, then one of R5 and R5a must be hydrogen and the other must be one of Formula (B), Formula (C), and Formula (D);
• R1, R2 R3 and R4 are each independently selected from the group consisting of:
• hydrogen, C1-7alkyl, C3-7cycloalkyl, halogen, azido, NR9R10, NHC(O)NR9R10, NHC(O)OR9, C(O)OR9, SR9, and OR9, wherein said C1-7alkyl is optionally substituted with one or more substituents selected from the group consisting of halogen, CN, OR9 SR9 and NR9R10;
• or R1 and R2 together form ═N—OH, ═O or —NR9R10;
• or R3 and R4 together form ═N—OH, ═O or —NR9R10;
• W is selected from the group consisting of hydrogen, C1-7alkyl, C3-7cycloalkyl, halogen, azido, NR9R10, NHC(O)NR9R10, NHC(O)OR9, N—OH, O and OR9, wherein said C1-7alkyl is optionally substituted with one or more substituents selected from the group consisting of halogen, CN, OR9 and NR9R10;
• R7 and R8 are each independently OH or H or together form ═O;
• R9 and R10 are each independently selected from the group consisting of:
• hydrogen, C1-7alkyl and C3-7cycloalkyl, wherein said C1-7alkyl is optionally substituted with one or more substituents selected from the group consisting of halogen, CN, OH, O—C1-7alkyl, NH2 and N(C1-3alkyl)2;
• or
• R9 and R10 together with the nitrogen atom to which they are attached form a non-aromatic 5-8 membered heterocycle containing one or two of the same or different heteroatoms selected from the group consisting of O, N and S;
• and
• X1, X1′, X2, and X2′ are each independently selected from the group consisting of hydrogen, halogen,
• cyano, OR9, —CF3, alkylcarbonly, C1-7alkyl, nitro, NR9R10, SR9 and C(O)OR9;
• wherein said C1-7alkyl is optionally substituted with one or more substituents selected from the group consisting of halogen, CN, OR9, SR9 and NR9R10.