Prostaglandin monolayers II: monomolecular film behavior of dinoprost C-15 alkyl esters.
Monomolecular film compression-relaxation behavior was examined for select dinoprost C-15 alkyl esters. Higher homologs of the series such as palmitate and decanoate esters yielded stable expanded monolayers that exhibited minimal relaxation of surface pressure during noncompression. Their limiting molecular areas were consistent with a Hirschfelder model projection in which the prostaglandin moiety assumes a horizontal orientation at the interface with its alkyl ester chain oriented vertical to the surface plane. Shorter chain homologs such as hexanoate, valerate, butyrate, propionate, and acetate also formed expanded monolayers but exhibited increased instability with decreased alkyl chain length, as reflected in their lower surface pressure development during compression and significant relaxation of pressure during noncompression. Such instability can be tied to their increased solubility in the subphase solution and higher desorption rate from the interface.
D055598:Chemical Phenomena; D002621:Chemistry; D008567:Membranes, Artificial; D008956:Models, Chemical; D008958:Models, Molecular; D008968:Molecular Conformation; D011460:Prostaglandins F; D011465:Prostaglandins, Synthetic; D013329:Structure-Activity Relationship; D013499:Surface Properties; D013500:Surface Tension; D013816:Thermodynamics
D008567:Membranes, Artificial; D011460:Prostaglandins F; D011465:Prostaglandins, Synthetic