GB875353A - Improvements in or relating to the preparation of diaminopimelic acid and an intermediate hydantoin derivative therefor - Google Patents

Abstract

The invention comprises (1) Trimethylenebis-(5,51)-hydantoin; (2) the preparation of the above compound by hydrolysing a 2-alkoxy-or 2-aryloxy-3,4-dihydro-2H-pyron or a 2,6-dialkoxy-or a 2,6-diaryloxy-tetrahydropyron followed by reaction of the resulting glutaraldehyde with cyanide ions, ammonium ions and carbonate ions in an aqueous medium; and (3) the preparation of alpha, epsilon-diaminopimelic acid by hydrolysis of the above hydantoin derivative. The hydrolysis of the pyron starting materials is preferably carried out at temperatures ranging between 15 and 45 DEG C. in presence of a dilute mineral acid or a cation exchange resin in the acid form. The glutaraldehyde intermediate may be reacted simultaneously with the cyanide, ammonium and carbonate ions to form the bis-hydantoin, or may be reacted first with the cyanide ions to form an intermediate cyanhydrin which is then further reacted with the ammonium and carbonate ions. The requisite ions may be supplied in the form of hydrogen cyanide, ammonia, carbon dioxide and ammonium carbonate. The hydrolysis of the bis-hydantoin derivative is preferably carried out at temperatures ranging from 100 to 250 DEG C. using strong acids such as hydrochloric, hydrobromic, sulphuric or sulphurous acids or using strong bases such as sodium, potassium or barium hydroxides. In either event the diaminopimelic acid is obtained as the salt corresponding to the hydrolysing agent. Specification 820,267 is referred to.