| abstract |
1,164,183. Pyridoxal. KYOWA HAKKO KOGYO K.K. 1 June, 1967 [2 June, 1966], No. 25296/67. Heading C2V. [Also in Division C3] Purified pyridoxal is made by hydrolysing with acid or alkali Schiff-bases which are reaction products of pyridoxal and waterinsoluble high molecular weight polymers of molecular weight not less than 1000 and containing primary amino groups as follows: |