the reaction of prostaglandins e1 , e2 , a1 and a2 with a 1:1 mixture of n , o-bis-trimethylsilyltrifluoroacetamide and piperidine favours the quantitative enolization of the 9-keto group of prostaglandins e , thus giving the corresponding tetrakis-tms derivatives with molecular ions at m/e 642 and m/e 640 for prostaglandins e1 and e2 , respectively , and also gives a new type of prostaglandin a-piperidyl-tms derivative characterized by very strong base peaks at m/e 464 and 462 , with molecular ions at m/e 637 and 635 for prostaglandins a1 and a2 , respectively .
C0002335
prostaglandins e1
C0033554
prostaglandin