ISSN print edition: 0366-6352 ISSN electronic edition: 1336-9075 Registr. No.: MK SR 9/7 Published monthly

Use of dodecanoyl isothiocyanate as building block in synthesis of target benzothiazine, quinazoline, benzothiazole and thiourea derivatives

Magdy M. Hemdan and Eman A. El-Bordany

Department of Chemistry, Faculty of Science, Ain Shams University, 11566 Abbasia, Cairo, Egypt

E-mail: mhemdan39@hotmail.com

Abstract: Dodecanoyl isothiocyanate (I) reacts additively with anthranilic acid to afford derivatives of thiourea II and benzothiazine III in a one-pot reaction. The cyclisation of thiourea II was achieved using acetic anhydride to form quinazoline derivative IV. The heating of quinazoline IV in acetic anhydride or butan-1-ol gave quinazoline derivatives V or VI, respectively. Benzothiazine III underwent trans-acylation to benzothiazine VII in boiling acetic anhydride. The treatment of IV with hydrazine hydrate, anthranilic acid or ethyl carbazate afforded derivatives of triazoloquinazoline VIII, quinazolinoquinazoline XI or thiosemicarbazide X, respectively. The reaction of I with 2aminophenol or 2-aminothiophenol afforded thiourea derivative XIII or benzothiazole derivative XIV, respectively. Most of the synthesised compounds bear a lauroyl (dodecanoyl) group (a hydrocarbon moiety). The structures of the synthesised compounds were confirmed by microanalytical and spectral data.

Keywords: lauroyl isothiocyanate – thiourea – benzothiazine – quinazoline – thiosemicarbazide derivatives

Full paper is available at www.springerlink.com.

DOI: 10.1515/chempap-2016-0042

Chemical Papers 70 (8) 1117–1125 (2016)