Synthesis of O--(14)-N-acetylnormuramoyl-L-α-aminobutanoyl-D-isoglutamine, lipophilic disaccharide analogues of MDP

Article abstract of DOI:10.1016/0008-6215(94)84291-4

Silver triflate-promoted condensation of 3,4,6-tri-O-acetyl-2-deoxy-2-phthalimido-β-D-glucopyranosyl bromide (1) with benzyl 2-acetamido-6-O-benzyl-2-deoxy-3-O-(methoxycarbonyl)methyl-α-D-glucopyranoside (4) afforded the key compound, benzyl 2-acetamido-6-O-benzyl-2-deoxy-3-O-(methoxycarbonyl)methyl-4-O-(3,4,6-tri-O-acetyl-2-deoxy-2-phthalimido-β-D-glucopyranosyl)-α-D-glucopyranoside (5), which after deprotection was transformed into acid 10.Condensation of 10 with the benzyl ester of L-α-aminobutanoyl-D-isoglutamine and deisopropylidenation of the product 11 afforded the benzyl ester of N-<2-O-glycoloyl>-L-α-aminobutanoyl-D-isoglutamine (12).Partial O-acylation of 12 and hydrogenolysis of protecting groups gave the 6-O-stearoyl- and 6-O-(2-tetradecylhexadecanoyl)-disaccharide-dipeptides 17 and 18, respectively.Pyrogenicity and adjuvant activity in cell-mediated immunity are reported.