Cyclic and branched acyl chain galactoglycerolipids and their effect on anti-tumor-promoting activity

Abstract

Fifteen new galactoglycerolipid analogues, in which one or two branched, alicyclic or aromatic acyl chains are linked to 2- O-β- d-galactosylglycerol (6′-position or 1,6′ positions), were prepared and tested for their anti-tumor-promoting activity using a short-term in vitro assay for Epstein–Barr virus early antigen (EBV-EA) activation. All compounds were active in inhibiting the EBV activation promoted by the tumor promoter 12- O-tetradecanoylphorbol-13-acetate (TPA), the branched compounds resulting in the most active glycoglycerolipid analogues of the series. The branched 2- O-[6- O-(3-methylbutanoyl)-β- d-galactopyranosyl]- sn-glycerol ( 1a) and the structurally related alicyclic 2- O-[6- O-(2-cyclohexylethanoyl)-β- d-galactopyranosyl]- sn-glycerol ( 1d), when tested in an in vivo two-stage carcinogenesis test, exhibited inhibitory effects on mouse skin tumor promotion.