Intermediates in the synthesis of camptothecin and related compounds and synthesis thereof

Abstract

A method of synthesizing compounds having the formula via a 4+1 radical annulation/cyclization wherein the precursor is reacted with an aryl isonitrile having the formula wherein X is selected from the group consisting of Br and I, ≡Y is ≡N or ≡C—R3, R1, R2, and R6 are independently hydrogen, a normal alkyl group, a branched alkyl group, an allyl group, a benzyl group, an alkynyl group, a propargyl group, an alkoxyl group, a halogen group, a trialkylsilyl group, an amino group, an alkyl amino group, a dialkylamino group, an aminoalkyl group, a cyano group, or R16CO—, wherein R16 is an alkyl group, an alkoxyl group, or an amino group, R3 is hydrogen, a normal alkyl group, a branched alkyl group, an allyl group, a benzyl group, an alkynyl group, a propargyl group, an alkoxyl group, a halogen group, a trialkylsilyl group, an amino group, an alkyl amino group, a dialkylamino group, an aminoalkyl group, a cyano group, or R16CO—, wherein R16 is an alkyl group, an alkoxyl group, or an amino group, R4 is an alkyl group, an allyl group, a propargyl group or a benzyl group and R15 is hydrogen.

Dependencies are inferred from the claim text.