Protected D-mannose derivs. - for prodn. of 2-keto-3-deoxy-D-manno-octonic acid bacterial lipo-polysaccharide components

摘要

D-Mannose derivs. of formula (I) are new; where X = O or a gp. of formula X1; where R5 = CH2Ar or 1-6C alkyl; R1-R4 = 1-3C alkyl, or R1+R2 and/or R3+R4 may form a 5- or 6-membered ring; Ar = phenyl substd. by 0-2 of 1-4C alkyl or alkoxy. Intermediates of formula (III) are also new. Prodn. of 2-keto-3 -deoxy-D-manno -octonic acid derivs. of formula (II) is effected by catalytic hydrogenolysis of cpds. (I; X=X1); where R6 = H or 1-6C alkyl. USE - Cpds. (II) are useful as intermediates for synthesis of bacterial lipopolysaccharides with immunostimulant and antitumour activity.