Abstract:
Phospholipids containing photolysable carhene precursors (beta-trifluoro-a-diazopropionoxy and m-diazirinophenoxy
groups) in w-positions of sn-2 fatty acyl chains were prepared. Photolysis of their vesicles produced crosslinked
products in 40-60 % yields. Crosslinking was mostly intermolecular and occurred bv carbene insertion into the C-H bonds
of a second fatty acyl chain. Crosslinking products were characterized by (i) their gel permeation behavior, (ii) analysis of
produets formed by base-catalyzed transesterification. (iii)
degradation with phosphoiipases A2 and C, (iv) gas chromatography/mass spectrometry, and-(v) use of mixtures of phospholipids
carrying thf' carhene precursors and a phospholipid containing radioactively labeled fatty acyl groups. Nitrenes
generated from the aliphatic or aromatic azido groups in phospholipids were unsatisfactory for forming crosslinks by
insertion in C-H bond
