| 摘要 |
Compounds having one of the formulae: <FORM:0858326/IV(b)/1> or <FORM:0858326/IV(b)/2> wherein n is 1 to 3, R is an alkyl, hydroxyalkyl, carboxyalkyl, aryl, carboxyphenyl, sulphophenyl or aralkyl group or a cation such as hydrogen, sodium, potassium, silver or ammonium, and the side chain is joined in the 2- or 4- position of the heterocyclic ring, are prepared according to a method described in U.S.A. Specification 2,810,724 by addition of a mercapto acid HS,(CH2) n COOH to 2- or 4- vinylpyridine or quinoline in the presence of a polymerization inhibitor such as hydroquinone. The free acid so produced may be converted into its salts or esters by known methods. An example is given of the reaction of mercapto-acetic acid with 4-vinyl-pyridine. |
