Total Syntheses and Cytotoxic Evaluations of Cryptolactones A₁, A₂, B₁, B₂, and Their Derivatives

Abstract

The cryptolactones A 1 , A 2, B 1 , and B 2 isolated from a Cryptomyzus sp. aphid were synthesized via the Mukaiyama aldol reaction and olefin metathesis. Their antipodes and derivatives were also synthesized by the same strategy to investigate structure-activity relationships. These compounds exhibited cytotoxic activity against human promyelocytic leukemia HL-60 cells with IC 50 values of 2.1-42 µM.

Mukaiyama aldol reaction: an effective asymmetric approach to access chiral natural products and their derivatives/analogues

“…62 These are found to be effective against various diseases as they inhibit the human immunodeficiency virus activity and interrupt the uncontrolled cell division. Inai et al , 63 reacted compound 70 through a number of steps to obtain aldehyde 71 , which was further subjected to react with TMS-substituted moiety 72 via a boron trifluoride diethyl etherate catalyzed Mukiyama aldol reaction to give 73a , 73b and 73c in 59%, 52% and 40% yields, respectively. Each of them was reacted with a Grubbs second generation catalyst in DCM to synthesize a mixture of 74a and 75a (caprolactones A 1 and A 2 ), 74b and 75b (caprolactones B 1 and B 2 ) and 74c and 75c in 79%, 69% and 60% yields, respectively (Scheme 9).…”