Optically active '--methylbenzyl-l-propyl-2,4-dimethyl-1,4-dihydronicotinamide, a chiral model of NAD(P)H, has been synthesized and its absolute configuration has been determined. It has been found that the model compound exerts high enantiospecificity in the reduction of certain carbonyl compounds in the presence of magnesium perchlorate. The results seem to show that the enantiospecificity is controlled by both the electronic and steric effects of substituents in the carbonyl compounds. The polar substituent of the substrate undergoing reduction faces the carbamoyl group of the model compound in the transition state for the reaction.

Chemical modification of the herbicide 1-[2-(benzothiazol-2-yl)isopropyl]-4-methyl-3-phenyl-5H-pyrrolin-2-one (MI-2826) has revealed a new oxazinone herbicide, 3-[2-(7-chlorobenzothiazol-2-yl)isopropyl]-2,3-dihydro-6-methyl-5-phenyl-4H-1,3-oxazin-4-one (MI-3069), for use in paddy fields. In comparing the phyototoxicity of the two herbicides to transplanted rice, the latter was superior to the former and kept the same predominant characteristic to control Echinochloa oryzicola Vasin for a long period of time owing to its long-lasting residual effect.

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The title reaction with N-(R)-a-methylbenzyl-1-propyl-2-methyl-4-(R) -methyl-1,4-dihydronicotinarnide or its 4-(S)-methyl isomer affords methyl mandelate in 97 yo optical yield and quantitative chemical yield.