The infrared hydroxyl and carbonyl stretching absorption spectra of salicylic, mandelic, and α-hydroxyisobutyric acids have been measured in dilute carbon tetrachloride solutions. The spectral data indicate that the first two acids exist exclusively in an internally-bonded conformation, one where the phenolic and the alcoholic hydroxyl groups form a hydrogen bond with the carbonyl oxygen atom of the cis-carboxyl structure, while the last acid takes, apart from such a conformation, another internally-bonded conformation, one where the hydroxyl group of the trans-carboxyl structure interacts with the alcoholic oxygen atom.

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Absorption, translocation and metabolism of mepanipyrim, N-(4-methyl-6-prop-lynylpyrimidin-2-yl)aniline in tomato seedlings were studied using 14C-preparations labeled separately in the pyrimidine and the benzene rings. When [14C]mepanipyrim was topically applied onto the leaf surface, most of the recovered radioactivity remained on the treated leaf. Unchanged mepanipyrim and a lot of metabolites were detected in the treated leaf. 2-[4-Methyl-6-(1-propynyl)pyrimidin-2-ylamino]-phenol (M-37), 4-[4-methyl-6-(1-propynyl)pyrimidin-2-ylamino]phenol (M-1), 1-(2-anilino-6-methylpyrimidin-4-yl)-2-propanol (M-31), and 4-methyl-6-(l -propynyl)pyrimidin-2-ylamine (M-41) were tentatively identified as major metabolites. M-37 and M-31 were mainly detected as several kinds of glycosides. When [14C] mepanipyrim was applied in an aqueous solution, the radioactivity in the seedlings increased with time, and 1-(2-anilino-6-methylpyrimidin-4-yl)-2-propanone (M-6) was also identified in the seedlings. A large amount of M-3l was detected in the seedlings when M-6 labeled with 14C was applied to seedlings in the same method as the parent compound. It is suggested that mepanipyrim is metabolized to M-31 via M-6.

The infrared carbonyl-stretching absorption bands of several methoxy-and hydroxyalkanoates have been measured in dilute carbon tetrachloride solutions, and their frequency shifts from the normal bands of ethyl alkanoates have been explained in terms of the dipolar-field and the hydrogen-bonding effects of the substituents. Further, as regards the direction of hydrogen bonding, the spectral data of the hydroxy-esters lead to essentially the same conclusion as that based on their hydroxyl spectra. However, the magnitudes of the carbonyl-frequency shifts due to hydrogen bonding can not be related to those of the corresponding hydroxyl shifts.