A Novel Heterocyclic Compound. Synthesis and Reactivities of an Oxazolo[3, 2-a]thieno[3, 2-d]pyrimidine Derivative

• Published in: Chemical & pharmaceutical bulletin Vol. 37; no. 5; pp. 1197 - 1200
• Main Authors: FUKUMI, Hiroshi, SUGIYAMA, Mitsuo, SAKAMOTO, Toshiaki
• Format: Journal Article
• Language: English
• Published: Tokyo The Pharmaceutical Society of Japan 1989; Maruzen; Japan Science and Technology Agency
• Subjects: 2-chloroethyl isocyanate; Animals; anti-gastric secretion activity; Anti-Ulcer Agents - chemical synthesis; Chemical Phenomena; Chemistry; Exact sciences and technology; Heterocyclic compounds; Heterocyclic compounds with n hetero atom and also o and/or s, se, te hetero atoms; Organic chemistry; oxazole-ring opening; Oxazoles - chemical synthesis; Oxazoles - pharmacology; oxazolopyrimidine; oxazolothienopyrimidine; Preparations and properties; Pyrimidinones - chemical synthesis; Pyrimidinones - pharmacology; Structure-Activity Relationship; Sulfur nitrogen heterocycle; Aminoester; Oxygen sulfur nitrogen heterocycle; Bicyclic compound; Aminosulfide; Tricyclic compound; Biological activity; Nucleophilic addition
• ISSN: 0009-2363; 1347-5223
• DOI: 10.1248/cpb.37.1197

A practical preparation of 2, 3-dihydro-5H-oxazolo[3, 2-a]thieno[3, 2-d]pyrimidin-5-oen (2) from methyl 3-aminothiophene-2-carboxylate in two steps was developed. The addition reactions of various nucleophiles to 2 were investigated and oxazole-ring-opened compounds were produced (5, 6, 12, 13 and 14). Desulfurization reaction of 2 with Raney Ni gave an oxazolo[3, 2-a]pyrimidine derivative (15). It was found that 2 showed potent anti-gastric secretion activity.