Photoswitchable glycolipid mimetics: Synthesis and photochromic properties of glycoazobenzene amphiphiles.

Glycolipids as constituents of cell membranes play an important role in cell membrane functioning. To enable the structural modification of membranes on demand, embedding of photosensitive glycolipid mimetics was envisioned and novel amphiphilic glycolipid mimetics comprising a photoswitchable azobenzene unit were synthesized. In this study, the photochromic properties of these glycolipid mimetics were analyzed by means of UV/Vis spectroscopy and reversible photoswitching. The glycolipids were based on a racemic glycerolipid derivative to be comparable in DPPC (dipalmitoylphosphatidylcholine) phospholipid membrane monolayers. Carbohydrate head groups were altered between a beta-glucoside and a beta-lactosyl unit, as well as acyl chain lengths between C12 and C16, resulting in altered photoswitching. Langmuir isotherms showed that photoswitching of Langmuir films comprising the synthetic photosensitive glycoamphiphiles was successful.