Stability of various alpha-esters of 1-(N-methyl-N-nitrosamino)-methanol in vitro and in vivo.

The hydrolytic activities of various rat tissue homogenates on the substrates 1-(N-methyl-N-nitrosamino)-methylacetate (NNMA), 1-(N-methyl-N-nitrosamino)-methylbutyrate (NNMB), 1-(N-methyl-N-nitrosamino)-methylbenzoate and 1-(N-methyl-N-nitrosamino)-methylpivaloate (NNMP) were investigated+. The hydrolytic enzymes of liver and serum showed similar activities toward all investigated compounds, while those of kidney, lung, heart, stomach and forestomach hydrolyzed the various esters differently. Differences in the in vivo elimination of NNMA, NNMB and NNMP from blood could not be found. After 20 s only 10% of the initial concentrations still occurred in blood after i.v. application.