ABSTRACT
We have identified phosphatidylethanolamine as one of the major phospholipids of Clostridium perfringens by two dimensional thin layer chromatography of the intact lipids and of their deacylation products and by liquid chromatography followed by mass spectrometry of the intact neutral phospholipid fraction. The principal fatty acids of phosphatidylethanolamine are myristic acid (14:0), lauric acid (12:0), and palmitic acid (16:0) and the major molecular species are 14:0,14:0 (26.3%); 12:0,14:0 (19.0%); 14:0,16:0 (22.4%) and 16:0,16:0 (17.6%). A similar distribution of molecular species was found in the other major phospholipid, O-alanyl phosphatidylglycerol.
Subject(s)
Clostridium perfringens/chemistry , Phospholipids/analysis , Phospholipids/chemistry , Chromatography, Liquid , Chromatography, Thin Layer , Fatty Acids/chemistry , Fatty Acids/isolation & purification , Lauric Acids/chemistry , Lauric Acids/isolation & purification , Mass Spectrometry , Myristic Acid/chemistry , Myristic Acid/isolation & purification , Palmitic Acid/chemistry , Palmitic Acid/isolation & purification , Phosphatidylethanolamines/analysis , Phosphatidylethanolamines/chemistry , Phosphatidylethanolamines/isolation & purification , Phosphatidylglycerols/analysis , Phosphatidylglycerols/chemistry , Phosphatidylglycerols/isolation & purificationABSTRACT
Oxidation of dexamethasone in an aqueous suspension by air during prolonged storage produces the 17alpha-formyloxy-17beta-carboxylic acid 4. A pathway to 4 is proposed that involves Baeyer-Villiger-type oxidation of keto aldehyde 1 to mixed anhydride 5, followed by intramolecular formyl transfer. Synthetically, acid 3 was reacted with N,N'-carbonyldiimidazole followed by triethylammonium formate in order to generate the transient anhydride 5 en route to an authentic sample of 4.
