An effective approach to the synthesis of three ricinoleic acid derivatives containing pyrazole, pyrazoline, and hydrazide fragments has been developed, starting from castor oil and based on its initial conversion into methyl-()-12-oxo-octadec-9-enoate, isomerization into methyl-()-12-oxo-octadec-10-enoate, and interaction with hydrazine hydrate.
G. Yu. Ishmuratov (Wed,) studied this question.