A Short Synthesis of (S)‐(+)‐Siphonodiol.

Abstract

A short synthesis of the enantiomer of the polyacetylenic natural product siphonodiol is described. The synthesis is based on the strategy of taking advantage of the hidden symmetry of the target molecule and minimizing the use of protecting groups, thereby reducing the total number of steps and increasing the overall efficiency.

Polyacetylene diols with antiproliferative and driving Th1 polarization effects from the marine sponge Callyspongia sp.

“…These results suggest that 1-3 cause the death of HL-60 cells through an apoptotic process. Compounds 1-3 also showed antiproliferative activity in a dose-dependent manner [1: 10 lg/ml (viability 84%), 30 (14), 100 (1); 2: 10 (83), 30 (50), 100 (2); 3: 10 (91), 30 (10), 100 (1.5)] and IC 50 values were 22, 34, and 21 lg/ml in HCT-15 cells. The terminal diol moiety of the chain structure might therefore be important for the highly selective antiproliferative property of 1-3, because fractions including linear polyacetylene compounds, callyberynes A-C, showed very weak antiproliferative activity (%growth suppression of this fraction: 0% at 30 lg/ml, 30% at 100 lg/ml), but fractions including 1-3 showed stronger antiproliferative activity than those of callyberynes A-C (%growth suppression of this fraction: 60% at 30 lg/ml, 100% at 100 lg/ml; Fig.…”

“…On the other hand, a synthesis of the enantiomer, (S)-(? )-siphonodiol of the natural product siphonodiol (2) was completed in 2007 and its [a] D value was ?6.5°(c 0.004, MeOH)[14]. As callyspongidiol (1) only differs from 2 by one CH 2 and one acetylene group, the configuration of 1 [[a] D value = -7.9°(c 1.13, MeOH)] at C-2 was consistent with being R. Thus, callyspongidiol (1) was designated as (12Z,19Z)-docosa-12,19-diene-3,5,10, 21-tetrayne-1,2(R)-diol.…”