Synthesis of some nucleosides derivatives from L- rhamnose with expected biological activity

Practical procedures for production of variously blocked compounds from L-rhamnose have been developed. These compounds are highly useful as indirect β-L-rhamnosyl donors. This approach represents a new method for the synthesis of aromatic nucleoside analogues and the synthesis of ( 3S, 4S, 5S, 6R) 3, 4, 5-triacetoxy-2-methyl-7,9-diaza-1-oxa-spiro 4,5]decane-10-one-8-thione (7).