Synthesis of 1R-cis-Dibromovinyl-2,2-dimethylcyclopropanes of the Isoxazole and Pyrazole Series Based on (+)-3-Carene.

New 1,3-disubstituted 2,2-dimethylcyclopropanes of the isoxazole and pyrazole series were synthesized starting from (+)-3-carene. Olefination of the reductive ozonolysis product of (+)-4-acetyl-2-carene produced 1R-cis-3-(2,2-dibromovinyl)-2,2-dimethylcyclopropane, further reaction of which with hydroxylamine or hydrazines led to heterocyclic compounds. It was shown that 3,5-dimethylpyrazoles could be synthesized on the surface of Al2O3 using ultrasonic irradiation. Studies of the antimicrobial activity of heterocyclic derivatives of dibromovinyl-2,2-dimethylcyclopropane found significant fungicidal effects of pyrazoles 8, 10, and 11 with weak antibacterial activity. [ABSTRACT FROM AUTHOR]