Structure du mycoside C2 de Mycobacterium avium

Abstract

Mycoside C₂ from Mycobacterium avium is a mixture of two homologous peptidoglycolipids: C_2a (Formula III) and C_2b (Formula IV). Both have the following partial structure:

The C-terminal molecule of D-alanine esterifies the pseudoaldehydic function of 6-deoxy-L-talose in mycoside C_2a and that of $\text{3-O-}\text{methyl-6-deoxy-}\text{L}\text{-talose}$ in mycoside C_2b. One acetyl group is linked to 3,4-di-O-methylrhamnose and two acetyl groups to 6-deoxy-L-talose and to $\text{3-O-}\text{methyl-6-deoxy-}\text{L}\text{-talose}$.

the lipid moiety is an acid (or mixture of acids) RCOOH of approximate formula C₄₃H₈₆O₂ ± 3 CH₂, or C₄₆H₉₀O₃ ± 3 CH₂ bound by an amide linkage to the amino group of D-phenylalanine.