GB472459A - Improvements in or relating to synthesis of a thiazole compound and its salts - Google Patents

Abstract

4 - Methyl - 5 - b - hydroxyethyl - thiazole is prepared by condensing thioformamide with a 3-halogen derivative of 3-acetopropan-1-ol. The latter compounds may be prepared according to Specification 472,396. According to the example, 3-brom-3-acetopropan-1-ol is allowed to stand with thioformamide in alcohol solution; the resulting hydrobromide is treated with an alkali to liberate the free thiazole, which may then be converted into its salts such as the sulphate and picrolonate. By reaction with pyrimidine derivatives, products are formed which are analogous to the antineuritic vitamin. The Specification as open to inspection under Sect. 91 also describes the synthesis of thiazoles by condensing compounds of the type CH3CO.CHXR, in which X is halogen and R represents the group CH2.CH2.OH or a group which may be converted into it, with compounds of the type ZCS.NH2, in which Z is hydrogen or a group such as amino and sulphydryl which can readily be transformed into hydrogen. The Z group in the product of the formula <FORM:0472459/IV/1> may be converted into hydrogen when it is an amino group by treatment with nitrous acid and when it is a sulphydryl group by the action of an oxidizing agent such as nitric acid or hydrogen peroxide. Similarly, the group R may be transformed into CH2.CH2OH by reduction when it consists of CH2.COOH, CH2.CHO or CH2.COOC2H5, and when it is CH2.CH2Y the group Y may be converted into hydroxyl by the reactions described above. This subject-matter does not appear in the Specification as accepted. Thioformamide is prepared by allowing formamide to stand in dry ethereal solution with phosphorus pentasulphide.