Investigation of the origin of 0-methyl groups in griseofulvin using some14C-labelled substrates

I-^l4C-pyruvie acid, 3-¹⁴C-l-serine,¹⁴C-formic acid and¹⁴CO₂ were tested as possible sources of 0-methyl groups of griseofulvin produced byPenicillium griseofulvum. Entire radioactivity from pyruvic acid,l-serine and formic acid was found in the methoxyls of griseofulvin. By determining the activity of individual methoxyls its distribution was established, this being homogeneous only after formic acid.