Synthesis and isolation of 1-hydroxy-2-propyl 3-chlorocarbanilate from soybean plants treated with isopropyl 3-chlorocarbanilate

Abstract

The metabolism of isopropyl 3-chlorocarbanilate (CIPC) to form an alkyl hydroxylated metabolite in soybean shoots was indicated by alkaline hydrolysis-distillation of 3-chloroaniline from polar plant extracts. The presence of l-hydroxy-2-propyl 3-chlorocarbanilate (III) in hydroponically grown plants was confirmed by autoradiograms of two-dimensional TLC plates, both of III and the acetate derivative of III, ír of III on HPLC and ír of the heptafluorobutyrate derivative of III on GLC. The presence of III in soil-grown plants was confirmed by the alkaline hydrolysis-distillation of 3-chloroaniline from polar extracts, ír of the acetate of III on HPLC and GLC, and the mass spectral analysis of the acetate of III. Soil grown soybean shoots produce a higher percentage of III when compared to the aryl hydroxylated metabolites which are the predominant metabolites found in hydroponically grown plants.Synthetic III (mp 88.5-91.0 °C, 68%) was prepared by HC1 cleavage of l-triphenylmethoxy-2-propyl 3-chlorocarbanilate (V) (mp 138-139 °C, 82%) which was prepared from l-triphenylmethoxy-2-propanol (IV) and 3-chlorophenyl isocyanate.Hodgson (1967) reported two water-soluble metabolites of isopropyl 3-chlorocarbanilate in barley, cucumber, and soybean. James and Prendeville (1969) reported the isolation of suspected d-glycosidic conjugates and postulated that the isopropyl moiety of CIPC was oxidized by smartweed, tomato, and parsnip plants. Extensive studies of hydroponically grown soybeans by Mansager (1971-1973) showed the presence of the aryl hydroxylated metabolites, isopropyl 5-chloro-2-hydroxycarbanilate (I) and isopropyl 3-chloro-4-hydroxycarbanilate (II), but provided no indication of alkyl hydroxylation.Unpublished work at PPG Industries (1973) on soybean plants confirmed the presence of I and II but also indicated the presence of a third metabolite. This paper reports the joint investigation resulting in the identification of this third metabolite, l-hydroxy-2-propyl 3-chlorocarbanilate (HI).EXPERIMENTAL SECTION Synthesis of Metabolites. Compounds I and II were prepared by the method of Grunow et al. (1970). Preparation of the compounds by a different route has been described by Bobik et al. (1972).

Uptake, Translocation, and Metabolism of Propham by Wheat(Triticum aestivum), Sugarbeet(Beta vulgaris), and Alfalfa(Medicago sativa)

“…The proposed pathway for the metabolism of propham in wheat, sugarbeet, and alfalfa ( Figure 2) is based upon the re sults obtained in the present investigation and other work con cerning plant metabolism of propham and chlorpropham (10,23,24,25,26,27,28,29). In all species propham and chlor propham were ring hydroxylated in either the ortho or para position and rapidly conjugated to form polar metabolites.…”

“…The proposed path way for the metabolism of propham in alfalfa indicates that l-hydroxy-2-propyl-carbanilate is a metabolite of propham since it was detected in small amounts in excised leaf methanol extracts (Figure 2). A similar metabolite of chlorpropham was postulated for certain plants (10) and has since been con firmed (29).…”