Synthesis of 2'-O-methoxyethylguanosine using a novel silicon-based protecting group.
A short and efficient synthesis of 2'-O-methoxyethylguanosine (8) is described. Central to this strategy is the development of a novel silicon-based protecting group (MDPSCl(2), 2) used to protect the 3',5'-hydroxyl groups of the ribose. Silylation of guanosine with 2 proceeded with excellent regioselectivity and in 79% yield. Alkylation of the 2'-hydroxyl group of 6 proceeded with methoxyethyl bromide and NaHMDS and afforded compound 7 in 85% yield, without any noticeable cleavage of the silyl protecting group and without the need to protect the guanine base moiety. Finally, deprotection of 7 was achieved using TBAF and produced 8 in 97% yield.
Wen
Ke
K
Department of Chemistry and Biochemistry, University of California, San Diego, 9500 Gilman Drive, La Jolla 92093-0358, USA.
Chow
Suetying
S
Sanghvi
Yogesh S
YS
Theodorakis
Emmanuel A
EA
D000478:Alkylation; D006151:Guanosine / Q000138:chemical synthesis* / Q000737:chemistry*; D015394:Molecular Structure; D012825:Silicon / Q000737:chemistry*
D006151:Guanosine; D012825:Silicon