Phosphonate compounds mimic the first transition state from a C-4 chiral synthon, 3-buten-1,2-diol -and treated with n-pentylphosphonic dichloride and p-nitrophenol to occurring during enzymatic carboxyester hydrolysis of natural substrates by forming a covalent bond with the afford the corresponding diastereomeric phosphonates, which were acylglycerol analogs. Subsequent separation of catalytic serine. However, until now the organophosphorus compounds used in the inhibition studies more or less each of the phosphonate diastereomers A/B or ent-A/ent-B, performed by HPLC, led to four enantiopure stereoisomers resembled a natural triglyceride substrate. In order to elucidate the interfacial activation and the mechanism of that will be investigated as inhibitors of Human Pancreatic Lipase (HPL) and Human Gastric Lipase (HGL) using the action of lipases, specific inhibitors need to be prepared. To achieve this goal, enantiomerically pure sn-1,2-and sn-2,3-monomolecular film technique. O-didecanoylglycerol compounds were prepared -starting we have focused our research on a new class of inhibitors Fax: (internat.) ϩ 33-4/91027776 of lipases). These molecules have two chiral centers and, as