Structures of phenolic glycolipids from Mycobacterium kansasii.

From the lipid fraction of cells of Mycobacterium kansasii, four phenolic glycolipids K5, K6, K7 and K8, were isolated, in addition to three known phenolic glycolipids KI, KII and KIV. K5 was identified as a tetraglycosyl phenolic glycolipid whose sugar moiety was 2,6-dideoxy-4-O-methyl-L-alpha-arabinohexopyranosyl(1-->3)-4-O-pro pionyl-2-O-methyl-L-alpha-fucopyranosyl(1-->3)-2-O-methyl-L-alpha-rhamno pyranosyl-(1-->3)-2,4-di-O-methyl-L-alpha-rhamnopyranosyl(1-->) and phenolic glycolipid K6 as deacetyl-KI. Glycolipids K7 and K8 were triglycosyl phenolic glycolipids having the sugar moieties of 2-O-methyl-L-alpha-fucopyranosyl(1-->3)-2-O-methyl-L-alpha-rhamnopyranos yl(1-->3)-2,4-di-O-methy-L-alpha-rhamnopyranosyl(1-->) and 2-O-methyl-L-alpha-fucopyranosyl(1-->3)-2-O-methyl-L-alpha-rhamnopyranos yl(1-->3)-2-O-methyl-L-alpha-rhamnopyranosyl(1-->), respectively. Phenolic glycolipids K6 and K7 have been referred to as controlled degradation products of phenolic glycolipid KI previously. Also isolated was 5-mycolyl-beta-arabinofuranosyl(1-->2)-5-mycolyl-alpha-ar abinofurnosyl(1-->1')-glycerol, an analogue of glycolipid ai, originally isolated from Mycobacterium avium-Mycobacterium intracellulare complex, having mycolic acids of M. kansasii.