Microbial transformations of pergolide to pergolide sulfoxide and pergolide sulfone

Fifty-eight Microorganisms were investigated for their ability to effect the biotransformation of the ergoline alkaloid pergolide. A majority of these organisms formed pergolide sulfoxide, and a Helminthosporium species was investigated in greater detail since it yielded significant amounts of pergolide sulfoxide. A preparative-scale transformation afforded material which was identified as the sulfoxide based on melting point, spectral, and chromatographic comparison with authentic material as well as its conversion to pergolide by reduction with triphenylphosphine. An analytical high-performance liquid chromatographic determination of the enzymatic versus spontaneous air-oxidation of pergolide in growing cultures and controls showed negligible air-oxidation and an approximately 40% enzymatic conversion of pergolide to the sulfoxide. Several organisms, including Aspergillus alliaceus formed a second metabolite, pergolide sulfone, which was identified on the basis of co-chromatographic data.