Glycerophospholipid synthesis: improved general method and new analogs containing photoactivable groups.

Abstract

Current methods for phospholipid synthesis involving acylation of sn-glycero-3-phosphorylcholine, lysolecithins, and related glycerophosphate esters are not satisfactory. With NN-dimethyl4aminopyridine as a catalyst and moderate amounts of fatty acid anhydrides (1.2-1.5 mol equiv per OH group), diacyl or 1,2-mixed diacylphosphatidyicholines, Nprotected phosphatidylethanolamines, and phosphatidic acids now can be conveniently prepared in high yields (75-90%). New phospholipids containing photoactivable groups, such as trifluorodiazopropionyl, diazirinophenoxy, 2-nitro-4-azidophenoxy, m-azidophenoxy, and a,3-unsaturated keto groups, in the fatty acyl chains have been prepared. These phospholipids are of interest in studies of lipid-lipid and lipid-protein interactions in biological membranes.

Stability of drug-carrier emulsions containing phosphatidylcholine mixtures

“…The modified phospholipid, n-hexanoyl lysolecithin derivative (6-PC) was prepared by partial synthesis from Epikuron 200 as starting material. The fatty acid was split off in position 2 by enzyme phospholipase A 2 (Novo Nordisk, Bagsvaerd, Denmark) and the resulting lysolecithin was converted to the 2-hexanoyl derivative following the method described by Gupta et al [8].…”

The proton conducting F0-part of bacterial ATP synthases

“…Labelling was so far analyzed on the level of intact subunits of whole pro teins, or large fragments [57][58][59][60][61] modified residues has not been reported so far. The seeond group comprises phospholipid derivatives, bearing a phenylazidoprecursor, a phenyldiazirine [62][63][64][65][66][67], or a trifluoromethylphenyldiazirine [68]. In these eompounds, the photoreactive group is fixed and is expected to eross-link with defined regions of the protein.…”

“…They even insert into CH bonds of the aliphatic chain of phospholipids [67]. The aryldiazirines represent one type of carbene precursor.…”

Spontaneous and protein-mediated intermembrane transfer of the antiretroviral liponucleotide 3'-deoxythymidine diphosphate diglyceride

“…Its purity was determined by HPTLC and HPLC and was greater than 95% (Van Wijk et al, 1992). PyrPC, a convenient starting material for the synthesis of 3dTDP-pyrDG, was prepared from 1 -myristoyl-lysoPC and 1 O-pyren-1 -yldecanoic acid anhydride as described (Somerharju et al, 1985;Gupta et al, 1977). The reaction mixture was evaporated to dryness, dissolved in chloroform/methano1/25% ammonia/water (70:38:8:2 v/v), and pyrPC was purified on a silica column (2.2 X 12 cm) with the above solvent mixture as eluent.…”