The synthesis of cord factor analogs.

Abstract

The new disaccharides, crystalline 6-deoxy-$\alpha$-D-gluco-heptopyranosyl 6-deoxy-$\alpha$-D-gluco-heptopyranoside (36) and the corresponding dicarboxylic acid (6-deoxy-$\alpha$-D-gluco-heptopyranosyluronic acid) 6-deoxy-$\alpha$-D-gluco-heptopyranosiduronic acid (5) were synthesized. Preparation of per-O- acetyl-$\alpha$,$\alpha$-trehalose 6,6$\sp\prime$-ditriflate 15 from known 2,3,4,2$\sp\prime$,3$\sp\prime$,4$\sp\prime$- hexa-O-acetyl-$\alpha$,$\alpha$-trehalose, followed by cyanide displacement in the former and subsequent hydrolysis produced 5. The latter was acetylated to give the 2,3,4,2$\sp\prime$,3$\sp\prime$,4$\sp\prime$-hexaacetate 12 of 5 which was reduced to furnish the disaccharide 36. This approach was also extended to synthesize the analogous 2,3,4,2$\sp\prime$,3$\sp\prime$,4$\sp\prime$-hexabenzyl ether of the dinitrile 28 which was similarly hydrolysed, but only to the stage of the corresponding diamide. The peracetylated dicarboxylic acid 12 was converted to the dichloride and subsequently esterified with 1-octanol, to form the di-octyl ester. Similar esterification with C$\sb $, C$\sb $, C$\sb $ and C$\sb $ 1-alkanols produced the analogous diesters. Three new mycolyl derivatives were obtained in high yields. (Abstract shortened by UMI.)