Patent · US Expired

Preparation of riboflavin, and 4,5-dimethyl-N-(D)-ribityl-2-(O-alkoxyphenylazo)-aniline intermediates

US4656275A · kind A · utility

1Cited by

4References

4Claims

0Family size

Assignee

BASF SE

Inventors

Hansgeorg Ernst · Speyer, DE
Heinz Eckhardt · Ludwigshafen, DE
Joachim Paust · Schifferstadt, DE

Key dates

Filing date	May 3, 1985
Grant date	Apr 7, 1987
Priority date	—
Expiry date	May 3, 2005

Classification

Technology area (CPC C)Chemistry; Metallurgy
CPC primaryC07D475/14
WIPO fieldOrganic fine chemistry
WIPO sectorChemistry

Abstract

An improved process for the preparation of riboflavin by condensation of a 4,5-dimethyl-N-(D)-ribityl-2-phenylazoaniline derivative with barbituric acid in the presence of an acidic condensing agent in an organic solvent, wherein a 4,5-dimethyl-N-(D)-ribityl-2-(o-alkoxyphenylazo)-aniline of the formula IIa ##STR1## where R is alkyl of 1 to 4 carbon atoms, in particular methyl, is reacted with barbituric acid, as well as the novel intermediates of the formula IIa.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.