| 摘要 |
<p>PT--81962 A Prostacycline PGI2 analogue of formula VIII is made by (a) protecting the aldehyde function of 5-(acetyloxy) octahydro 2-oxo-cyclopenta (b) pyrrole 4-carboxyaldehyde by reaction with ethylene glycol catalysed by acid to form a 1,3-dioxolane; (b) treating with P2S5; (c) alkylating with methyl omega- bromo butyrate in presence of sodium hydride to obtain (V); (d) regenerating the aldehyde function by treatment under mild acid conditions; (e) reaction with 2-(acetyloxy) heptyl triphenyl phosphonium bromide under Wittig reaction conditions in basic medium to obtain the diacylated cpd. (VII); and (f) reaction with K2CO3 in methanol.</p> |
