| abstract |
Highly selective and high yield process for producing antitumor agent 1-phthalidyl-5-fluorouracil derivatives of formula (I) which comprises reacting a phthalidyl compound (II) with an amine (III) to yield the quaternary ammonium salts (IV), and reacting the latter with 5-fluorouracil. ##STR1## [wherein X is leaving group; ##STR2## is triethylamine, N-methylmorpholine, N-ethylmorpholine, and the like; R 4 and R 5 each is hydrogen, trialkylsilyloxy, alkoxy, nitro, cyano, carboxy, or alkoxycarbonyl]. |