New 1,3-benzoxazin-2-ones or thiones of molluscacidal activity.

A facile synthetic approach towards 3-aryl, alkyl or beta-glucopyranosyl-1,3-benzoxazin-2-ones and their thio-analogues 3 was adopted via the reaction of the easily available 3-(2-hydroxyaryl)-2-propen-1-ones 1 with a variety of isocyanates or isothiocyanates. The isolation of the open-chain carbamates 2 and then independent cyclization to the corresponding 1,3-benzoxazines 3 confirms the reaction sequence. Molluscacidal activity of the products was screened.