Defined multi-conjugates oligonucleotides

A method for synthesizing a compound according to Structure 7 or 8:

• wherein:
• each is a double stranded oligonucleotide, each • is a covalent linker joining single strands of adjacent single stranded oligonucleotides, and m is an integer ≥1 and n is an integer >0, the method comprising the steps of:
• (i) forming by:
• (a) annealing a first single stranded oligonucleotide and a second single stranded oligonucleotide R1, thereby forming R1, and reacting R1 with a third single stranded oligonucleotide R2, wherein R1 and R2 are chemical moieties capable of reacting directly or indirectly to form a covalent linker •, thereby forming ;
• or
• (b) annealing a first single stranded oligonucleotide and a first single stranded dimer , thereby forming ;
• (ii) annealing and a second single stranded dimer , thereby forming and, optionally, annealing one or more additional single stranded dimers to thereby forming,
• and
• (iii) annealing a fourth single stranded oligonucleotide to the product of step (ii), thereby forming structure 7 or 8.

The method of claim 1, for synthesizing the compound of Structure 8 wherein n is 0, comprising the steps of:

• (i) forming by:
• (a) annealing a first single stranded oligonucleotide and a second single stranded oligonucleotide R1, thereby forming R1, and reacting R1 with a third single stranded oligonucleotide R2 wherein R1 and R2 are chemical moieties capable of reacting directly or indirectly to form a covalent linker •, thereby forming ;
• or
• (b) reacting the second single stranded oligonucleotide R1 and the third single stranded oligonucleotide R2, thereby forming , and annealing the first single stranded oligonucleotide and , thereby forming ;
• (ii) annealing and , thereby forming ;
• and
• (iii) annealing and a fourth single stranded oligonucleotide , thereby forming .

The method of claim 1, for synthesizing the compound of Structure 7 wherein m is 1, comprising the steps of:

• (i) forming by:
• (a) annealing a first single stranded oligonucleotide and a second single stranded oligonucleotide R1, thereby forming R1, and reacting R1 with a third single stranded oligonucleotide R2, wherein R1 and R2 are chemical moieties capable of reacting directly or indirectly to form a covalent linker •, thereby forming ;
• or
• (b) reacting the second single stranded oligonucleotide R1 and the third single stranded oligonucleotide R2, thereby forming , and annealing the first single stranded oligonucleotide and , thereby forming ;
• (ii) annealing and a single stranded dimer , thereby forming ;
• (iii) annealing and a second single stranded dimer , thereby forming ;
• and
• (iv) annealing and a fourth single stranded oligonucleotide , thereby forming .