The mutagenicity of 17 aliphatic epoxides was determined using the specially constructed mutants of Salmonella typhimurium developed by Ames. The activity of these epoxides together with those reported in the literature as mutagens in strains TA100 and TA1535 depended on the degree of substitution around the oxirane ring. Monosubstituted oxiranes were the most potent mutagens in both strains. 1,1-Disubstitution resulted in the complete loss or reduction of mutagenicity, trans-1,2-Disubstituted, and tetrasubstituted oxiranes all lacked mutagenicity, while the cis-1,2-disubstituted oxiranes tested were weakly mutagenic in strain TA100 only. For the monosubstituted compounds the presence of electron-withdrawing substituents increased mutagenicity.

The alkylation of nicotinamide by a series of ten propylene oxides with subsequent formation of a chromophore In a new procedure Is compared to the conventional 4-(p-nltrobenzyl)pyrldlne (NBP) test. Both reactions exhibited similar rates of alkylation, competing rates of solvolysis and correlation of the extent of alkylation to the Taft * values of substituent groups. The nicotinamide procedure has the advantage that the Initial alkylation can be run under more physiological conditions and that there Is an Increase In the stability of the final chromophore.

This study reports the formation and isolation of a diethylstibestrol-dimethylsulfoxide (DES-DMSO) adjunct and Z-3, 4-di (p-hydroxyphenyl)-2-hexene (psi-DES) from trans-DES. The presence of psi-DES was indicated by NMR and mass spectrometry and confirmed by direct comparison to a reference sample. High resolution NMR (360 MHz) along with the comparison of the chemical shift values of methine and methyl protons attached to carbon-carbon double bonds in Z and E isomers of 3-substituted-2-pentenes and dienestrol derivatives were used in postulating the Z-stereochemistry for psi-DES. A NMR additive increment method was useful for the comparison of the chemical shift values of methine protons in psi-DES and other literature compounds. Nuclear Overhauser Enhancement (NOE) confirmed the Z-stereochemistry of psi-DES.

The CH2C12 was washed with saturated NaCl solution, dried (K2C03), and concentrated on a rotary evaporator to give 0.69 g (84% crude) of 2. This was distilled to give 0.31 g (38%) of pure 2: bp 110 °C (0.07 mm); NMR (CDC13) 0.95-2.02 (m, 8, H3, H6, H7, and NH2), 2.12 (broad s, 1, Hi), 2.45 (d, 1, H4), 2.54-3.14 (m, 2, H2 and Hg), 7.14 (q, endo-py 0-H), 7.27 (q, exo-py 0-H), 8.47 (q, 2, py a-H).

Aus dem Acetessigester‐Anion (I) und Chloracetessigester (II) entsteht das "Dimere" (III), das zu authentischem Diacetyl‐maleinester (IV) oxidiert werden kann.