Metabolism of Isoxathion,O,O-Diethyl O-(5-Phenyl-3-isoxazolyl)-phosphorothionate in Plants

The absorption and metabolism of the insecticide, Isoxathion, on bean, cabbage and Chinese cabbage plants were examined using carbon-14 labeled compound. Isoxathion penetrated into plant tissues was hydrolyzed to produce 3-hydroxy-5-phenylisoxazole, which was then rapidly converted to water soluble compounds. Among them, 3-(β-d-glucopyranosyl-oxy)-5-phenylisoxazole, 2-(β-d-glucopyranosyl)-5-phenyl-4-isoxazolin-3-one and 2-(β-d-glucopyranosyl)-5-p-hydroxy-phenyl-4-isoxazolin-3-one were unequivocally identified as the major metabolites. Another metabolic pathway of 3-hydroxy-5-phenylisoxazole via a reductive cleavage of the isoxazole ring to form benzoic acid was negligible.     

Metabolism of Isoxathion,O, O-Diethyl O-(5-Phenyl-3-isoxazolyl) phosphorothioate in the Rats

Excretion, distribution and metabolism of the insecticide, Isoxathion, administered orally in male Wistar-strain rats, were investigated with a carbon-14 labeled chemical. During 96 hr, approximately 85% and 14% of the total radioactivity were excreted in the urine and feces. Distribution of isoxathion after oral administration in the rats was investigated by means of whole-body autoradiographic technique and measurement of radioactivity in the tissues. At least eleven radioactive metabolites were detected, four of which were structurally determined. They were 3-hydroxy-5-phenylisoxazole, 3-(β-d-glucopyranuronosyloxy)-5-phenylisoxazole, 5-phenyl-3-isoxazolyl sulfate and hippuric acid.     

Photolysis of 3-Hydroxyisoxazoles

Photolysis of 3-hydroxy-5-phenylisoxazole in methanol with a low-pressure mercury lamp afforded 5-phenyl-4-oxazolin-2-one, together with small amounts of benzoic acid and benzoylacetamide. Similarly, 3-hydroxy-5-methylisoxazole in distilled water afforded 5-methyl-4-oxazolin-2-one as the major product. Both isoxazoles were stable in sunlight for up to 20 days.     

Comparative placental steroid synthesis. II. C19 steroid metabolism by guinea-pig placentas and fetal adrenals in vitro

Placental homogenates from guinea-pigs at 16, 20, 35 and 55 days gestation were incubated with 7α-³H-dehydroepiandrosterone and 4-¹⁴C-androstenedione and analyzed for conversion products by reverse isotope dilution methods. ¹⁴C-3α-Hydroxy-5α-androstan-17-one, ¹⁴C-androstane-3α, 17β-diol and ³Handrost-5-ene-3β, 17β-diol were isolated from homogenates incubated with substrates for 2 hours. ³H, ¹⁴C-Testosterone was isolated from preparations incubated for 15 minutes or with high substrate: tissue ratios. Androst-4-ene-3, 17-dione, 5α-androstane-3, 17-dione, 5β-androstanedione derivative and C₁₈ steroid formation could not be demonstrated. These results demonstrate the capacity of guinea-pig placentas to convert dehydroepiandrosterone and androstenedione to testosterone and to derivatives reduced in ring A (5α) and at carbon 17. The activity of the Δ⁵-3β-hydroxysteroid dehydrogenase enzyme system appears to have been rate limiting.Homogenates of adrenals from 44–55 day old fetuses converted 4-¹⁴C-pregnenolone to androst-4-ene-3, 17-dione and 6β- and 11β-hydroxyandrostenedione. A guineapig fetal-placental unit is postulated, with steroid metabolic characteristics different from the human unit. Both permit reduction of fetal adrenal cortisol production and placental removal of C₁₉ steroids.     

Isolation of a buprofezin co-metabolizing strain of <Emphasis Type="Italic">Pseudomonas</Emphasis> sp. DFS35-4 and identification of the buprofezin transformation pathway

Buprofezin is a widely used insecticide that has caused environmental pollution in many areas. However, biodegradation of buprofezin by pure cultures has not been extensively studied, and the transformation pathway of buprofezin remains unclear. In this paper, a buprofezin co-metabolizing strain of DFS35-4 was isolated from a buprofezin-polluted soil in China. Strain DFS35-4 was preliminarily identified as Pseudomonas sp. based on its morphological, physiological, and biochemical properties, as well as 16S rRNA gene analysis. In the presence of 2.0 g l⁻¹ sodium citrate, strain DFS35-4 degraded over 70% of 50 mg l⁻¹ buprofezin in 3 days. Strain DFS35-4 efficiently degraded buprofezin in the pH range of 5.0–10.0 and at temperatures between 20 and 30°C. Three metabolites, 2-imino-5-phenyl-3-(propan-2-yl)-1,3,5-thiadiazinan-4-one, 2-imino-5-phenyl-1,3,5-thiadiazinan-4-one, and methyl(phenyl) carbamic acid, were identified during the degradation of buprofezin using gas chromatography–mass spectrometry (GC–MS) and tandem mass spectrometry (MS/MS). A partial transformation pathway of buprofezin in Pseudomonas sp. DFS35-4 was proposed based on these metabolites.     

Reactions of ketones with coordinated nitriles on β-diketonato ruthenium complexes leading to formation of compounds with new carbon-carbon bonds

The reactions of [Ru(acac)₂(CH₃CN)₂] with four ketones (acetone, ethyl methyl ketone, acetylacetone and monochloroacetone), and the reactions of [Ru(acac)₂(C₆H₅CN)₂] with two ketones (acetone and ethyl methyl ketone) yielded six novel compounds of β-ketiminato ruthenium complexes: [Ru(acac)₂(mhmk)], [Ru(acac)₂(ehmk)], [Ru(acac)₂(mAmk)], [Ru(acac)₂(mClmk)], Ru(acac)₂(mhbk)], and [Ru(acac)₂(ehbk)] (mhmk = 4-iminopentane-2-one mono anion, ehmk = 5-iminohexane-3-one mono anion, mAmk = 3-(1-iminoethyl)-2,4-pentanedione mono anion, mClmk = 3-chloro-4-imino-pentane-2-one mono anion, mhbk = 1-phenyl-1-iminobutane-3-one mono anion, ehbk = 1-phenyl-1-iminopentane-3-one mono anion). All the new complexes have been characterized by elemental analyses, ¹H NMR, MS and electronic spectral data. Crystal and molecular structures for the six β-ketimine complexes have been solved by single crystal X-ray diffraction studies. A mechanism involving the attack of ketones on the coordinated nitrile has been proposed. The electrochemical redox behavior of the β-ketimine complexes has been elucidated.     

Site selectivity in reactions of hydrazonoyl halides with heterocycles containing amino and thione groups leading to fused heterocycles of potential antimicrobial activity

Reaction of hydrazonoyl halides with 6-(benzylidenamino)-2-thioxo-2,3-dihydro-1H-pyrimidin-4-one and 2,3-diaminoquinazolin-4-one site-selectively afforded 3-substituted-7-(benzylidenamino)-1-phenyl-[1,2,4]triazolo[4,3-a]-pyrimidin-5(1H)-ones, [1,2,4,5]tetrazino[6,1-b]quinazolin-6(4H)-one, and 3-methyl-2-(4-substituted-phenylhydrazo)-[1,2,4]triazino[3,2-b]quinazolin-10-ones in good yields. The structures of the newly synthesized compounds were elucidated by chemical evidence and their IR, ¹H, ¹³C NMR, and MS spectra. Furthermore, some of the products were screened against different strains of bacteria and fungi.     

Microbial and xanthine dehydrogenase inhibitory activity of some flavones

Xanthine dehydrogenase (XDH) is responsible for the pathological condition called Gout. In the present study different flavones synthesized from chalcone were evaluated in vitro for their inhibitory activity. Inhibitory activity of flavones on XDH was determined in terms of inhibition of uric acid synthesis from Xanthine. The enzymatic activity was found maximum at pH 7.5 and temperature 40°C. The flavones 6-chloro-2-[3-(4–hydroxy-phenyl)-1-phenyl-1-H-pyrazol-4-yl]-chromen-4-one (F₁) and 6-chloro-7methyl-2-[3-(4-chloro-phenyl)-1-phenyl-1-H-pyrazol-4-yl]-chromen-4-one(F₂),were noncompetitive and competitive inhibitor with Ki values 1.1 and 0.22 respectively. The flavones (F₁), (F₂), 6-chloro-2-[3-(4-chloro-phenyl)-1phenyl-1-H-pyrazol-4-yl]-chromen-4-one(F₃), 8-bromo-6-chloro-2-[3-(4-chloro-phenyl)-1-phenyl-1-H-pyrazol-4-yl]-chromen-4-one (F₄), 2-[3-(4-hydroxy-phenyl)-1-phenyl-1-H-pyrazol-4-yl]-chromen-4-one (F₅) and 6-methyl-2-[3-(4-hydroxy-phenyl)-1-phenyl-1-H-pyrazol-4-yl]-chromen-4-one (F₆) were also screened for their antimicrobial activity, measured in terms of zone of inhibition. A broad spectrum antifungal activity was obtained against Trichoderma viridae, Candida albicans, Microsporum cannis, Penicillium chrysogenum and Fusarium moniliformae. In case of Aspergillus niger and Aspergillus flavous only spore formation was affected, while antibacterial activity was observed against Staphylococcus aureus, Bacillus subtilis and Serratia marsecens only. The flavones were further analyzed for quantitative structural activity relationship study (QSAR) by using PASS, online software to determine their Pa value. Toxicity and drug relevant properties were revealed by PALLAS software in terms of their molecular weight. Log P values were also studied. The result showed both the F₁ and F₂ flavones as antigout and therefore supports the development of novel drugs for the treatment of gout.     

Metabolism of 17-phenyl-18,19,20-trinor-prostaglandin F2α in the cynomolgus monkey and the human female

[9β-³H]-17-Phenyl-18,19,20-trinor-PGF₂α was injected subcutaneously into female Cynomolgus monkeys and the structures of six products appearing in the urine were determined. The main urinary metabolites were the dinor- and tetranor-derivatives of 15-keto-13,14-dihydro-17-phenyl-18,19,20-trinor-PGF₂α. Unchanged 17-phenyl-18,19,20-trinor-PGF₂α was also identified among the urinary products, as well as its dinor- and tetranor-derivatives. Finally, the dinor-derivative of 13,14-dihydro-17-phenyl-18,19,20-trinor-PGF₂α was also found in urine. The same six products were also found in urine from human female subjects that had received 17-phenyl-18,19,20-trinor-PGF₂α either subcutaneously or intravenously.Studies on the half-life of the compound in the circulation were also performed in human females. Two less polar metabolites in plasma were identified, viz. 13,14-dihydro-17-phenyl-18,19,20-trinor-PGF₂α and 15-keto-13,14-dihydro-17-phenyl-18,19,20-trinor-PGF₂α.     

Synthesis of new heterocyclic hybrids based on pyrazole and thiazolidinone scaffolds as potent inhibitors of tyrosinase

As a part of ongoing studies in developing new Tyrosinase inhibitors, a class of structurally novel 2-(2,4-dimethoxy phenylamino)-5 methylene-4-thiazolinone derivatives were synthesized by incorporating 2-(2,4-dimethoxy-phenylamino)-thiazol-4-one with various 1-(1-methyl-buta-1,3-dienyl)-3-phenyl-1H-pyrazole-4-carbaldehyde. The results showed that some of the synthesized compounds exhibited significant inhibitory activities. Especially, 5-[3-(2-chloro-phenyl)-1-phenyl-1H-pyrazol-4-ylmethylene]-2-(2,4-dimethoxy-phenylamino)-thiazol-4-one (5h) and 5-[3-(3-chloro-phenyl)-1-phenyl-1H-pyrazol-4-ylmethylene]-2-(2,4-dimethoxy-phenylamino)-thiazol-4-one (5g) possessing 2-chloro-phenyl and 3-chloro-phenyl group exhibited the most potent tyrosinase inhibitory activity with an IC₅₀ value of 34.12 and 52.62 μM, respectively. The inhibition mechanism analysis of 5h and 5g thiazolidinone derivatives demonstrated that the inhibitory effects of the compounds on tyrosinase were reversible and competitive. Preliminary structure–activity relationships (SAR) analysis suggested that further development of such compounds might be of interest, as it manifests simple reversible slow binding inhibition against monophenolase and diphenolase.     

Growth of Fusarium moniliforme on n-Alkanes: Comparison of an immobilization method with conventional processes

Summary In submerged culture there was negligible growth of Fusarium moniliforme with either n-tetradecane or gasoil (C₁₃–C₁₉) as the only carbon and energy source. In surface culture the cell yield was about 0.25 g dm^–3 dry weight after four weeks incubation. Some oxidation products, mainly isomeric tetradecanones (4-one, 5-one, 6-one and 7-one), could be identified. However the cell yield in a trickle-flow column was about 3 g dm^–3 dry weight after 7 days. Only traces of oxidation products could be detected. In a fixed-bed reactor, filled with glass rings, cell yields were similar to those in the trickle-flow column and depended on the medium flow rate.After termination of growth in the fixed-bed reactor, similar amounts of gibberellic acid were produced in a nitrogen-free medium with either gasoil or glucose.     

Effect of rice plants on methane production and rhizospheric metabolism in paddy soil

In order to elucidate the effects of rice plants on CH₄ production, we conducted experiments with soil slurries and planted rice microcosms. Methane production in anoxic paddy soil slurries was stimulated by the addition of rice straw, of unsterile or autoclaved rice roots, and of the culture fluid in which rice plants had axenically been cultivated. The addition of these compounds also increased the concentrations of acetate and H₂, precursors of CH₄ production, in the soil. Planted compared to unplanted paddy soil microcosms exhibited lower porewater CH₄ concentrations but higher CH₄ emission rates. They also exhibited higher sulfate concentrations but similar nitrate concentrations. Concentrations of acetate, lactate and H₂ were not much different between planted and unplanted microcosms. Pulse labeling of rice plants with¹⁴CO₂ resulted during the next 5 days in transient accumulation of radioactive lactate, propionate and acetate, and after the second day of incubation in the emission of¹⁴CH₄. Most of the radioactivity (40–70%) was incorporated into the above-ground biomass of rice plants. However, during a total incubation of 16 days about 3–6% of the applied radioactivity was emitted as¹⁴CH₄, demonstrating that plant-derived carbon was metabolized and significantly contributed to CH₄ production. The sequence of the appearance of radioactive products and their specific radioactivities indicate that CH₄ was produced from root exudates by a microbial community consisting of fermenting and methanogenic bacteria.     

The in vitro biosynthesis and metabolism of progesterone and estrogens by chimpanzee placental tissue

The biosynthesis and metabolism of progesterone and estrogens have been studied in chimpanzee placental tissue in vitro. The conversion of androstenedione-4-14C to estrone and estradiol-17β and of pregnenolone-7α-3H to progesterone has been demonstrated. In addition, the following metabolites were isolated following incubation of either pregnenolone-7α-3H or progesterone-4-¹⁴C: 20α-dihydroprogesterone, 20β-dihydroprogesterone, 6β-hydroxyprogesterone, 5α-pregnane-3,20 dione. The compound 5α-pregnan-3β o1-20-one was identified only after incubation with pregnenolone-7α-3H, while 5β-pregnane-3, 20 dione was identified only after incubation with progesterone-4-¹⁴C. No estrogens could be demonstrated following the incubation of placental preparations with either of the C₂₁ substrates.     

Inhibition of prostagland in E2-induced cyclic AMP accumulation in the rat anterior pituitary by II-deoxyprostaglandin E analogs (9-ketoprostynoic acids)

The effects of various II-deoxyprostaglandin E analogs on the basal and prostaglandin E₂ (PGE₂)-induced cyclic AMP accumulation in the rat anterior pituitary were studied in vitro. 13-Hydroxy-9-oxoprost-14-ynoic acid at 5 × 10⁻⁴M, but not 5 × 10⁻⁵M, decreased (45%) the induced accumulation and did not alter the basal accumulation; 15-hydroxy-9-oxoprost-13-ynoic acid at 5 × 10⁻⁴M caused less of a decrease (29%) in the induced and also did not alter the basal accumulation. (14Z)-13-Hydroxy-9-oxoprost-14-enoic acid at 5 × 10⁻⁴M did not alter the induced and caused a slight increase (5 fold) in the basal accumulation. 7-Oxa-13-prostynoic acid increased slightly the basal accumulation at 5 × 10⁻⁵M (2 fold) and 2.33 × 10⁻⁴M (6 fold) and did not antagonize the induced accumulation. Thus, the 9-ketoprostynoic acids are effective PGE₂ antagonists in this system.     

Inhibition of prostaglandin E2-induced cyclic AMP accumulation in the rat anterior pituitary by 11-deoxyprostaglandin E analogs (9-ketoprostynoic acids)

The effects of various 11-deoxyprostaglandin E analogs on the basal and prostaglandin E₂ (PGE₂)-induced cyclic AMP accumulation in the rat anterior pitutiary were studied . 13-Hydroxy-9-oxoprost-14-ynoic acid at 5 × 10⁻⁴M, but not 5 × 10⁻⁵M, decreased (45%) the induced accumulation and did not alter the basal accumulation; 15-hydroxy-9-oxoprost-13-ynoic acid at 5 × 10⁻⁴M caused less of a decrease (29%) in the induced and also did not alter the basal accumulation. (14Z)-13-Hydroxy-9-oxoprost-14-enoic acid at 5 × 10⁻⁴M did not alter the induced and caused a slight increase (5 fold) in the basal accumulation. 7-Oxa-13-prostynoic acid increased slightly the basal accumulation at 5 × 10⁻⁵M (2 fold) and 2.33 × 10⁻⁴M (6 fold) and did not antagonize the induced accumulation. Thus, the 9-ketoprostynoic acids are effective PGE₂ antagonists in this system.     

Bifunctional enzyme activity at the same active site: Competitive inhibition kinetics with 3α/20β-hydroxysteroid dehydrogenase

20β-Hydroxy-5α-pregnan-3-one (HPO) is a competitive inhibitor of reduction by 3a/20β-hydroxysteroid dehydrogenase (3α/20β-HSD; E.C.1.1.1.53) of 17β-hydroxy-5α-androstan-3-one (DHT; 3α-activity; K_i = 4.6 × 10^?5M) and of 6β-acetoxyprogesterone (6β-AP; 20β-activity; K_i = 4.34 × 10^?5M). HPO and DHT inhibit affinity alkylation of 3α/20β-HSD by 6β-bromoacetoxyprogesterone (6β-BAP). The facts that 1) enzyme 3α-activity and 20β-activity are both competitively inhibited by HPO with practically identical K_i-values, 2) 6β-BAP is solely a 20β-activity substrate for 3α/20β-HSD, 3) one mole of 6β-BAP reacts with one mole of 30/20β-HSD to simultaneously inactivate 3α- and 20β-activity and 4) inactivation of 3α/20β-HSD by 6β-BAP is inhibited by DHT (a Cig-steroid) or HPO (a C₂₁-steroid), support the view that the same active site of 3α/20β-HSD possesses both 3α- and 20β-activity. Bifunctional activity at the same active site is considered for other steroid-specific enzymes in female mammalian reproductive systems.     

Antioxidant activity of 3-methyl-1-phenyl-2-pyrazolin-5-one

Summary

The antioxidant activity of an anti-ischemic agent, 3-methyl-1-phenyl-2-pyrazolin-5-one (MCI-186), was examined. The pKa value of MCI-186 is 7.0 and the rate of oxidation of MCI-186 initiated with an azo compound increased with increasing pH, suggesting that the anionic form of MCI-186 is much more reactive than the non-ionic form. The major products were 3-methyl-1-phenyl-2-pyrazolin-4,5-dione (4,5-dione) and 2-oxo-3-(phenylhydrazono)-butanoic acid (OPB). Hydrolysis of 4,5-dione gave OPB. The minor intermediate product was 4-hydroxy-4-(3-methyl-1-phenyl-1H-pyrazolin-5-on-4-yl)-3-methyl-1-phenyl-1H-pyrazolin-5-one (BPOH). The nucleophilic attack of the anionic form of MCI-186 to 4,5-dione is likely to give BPOH. MCI-186 (50 μM) inhibited the aerobic oxidation at 37°C of 5.2 mM unilamellar soybean phosphatidylcholine (PC) liposomal membranes, initiated with a water-soluble initiator, as efficientlyas did ascorbate (100 μM). MCI-186 (50 μM) also inhibited the oxidation of the same PC liposomal membranes, this time initiated with a lipid-soluble initiator, almost as efficiently as did α-tocopherol (2 μM). Furthermore, the combination of MCI-186 with ascorbate or α-tocopherol showed almost complete inhibition of PC oxidation induced by both initiators. These data suggest that MCI-186 may work as a good antioxidant in cellular systems as well as in cell-free systems.     

The in vivo metabolites of [14C] progesterone in bovine muscle and adipose tissue

Muscle and adipose tissue were obtained from steers and dairy cows following subcutaneous administration of [¹⁴C] progesterone. Following extraction, purification and separation by column, thin layer and gas-liquid chromatography, various radioactive residues from these tissues were identified by their Chromatographic mobility, crystallization to constant specific activity and mass spectra. Progesterone constituted 54% of free radioactivity extracted from muscle and 69 and 73% of radioactivity in the free and conjugated portions of extracts, respectively, from fat. Metabolites identified were: 5α-pregnane-3,20-dione, 9%, 0%, 0%, 20β-hydroxy-4-pregnen-3-one, 8%, 11%, 3%; 3α-hydroxy-5β-pregnan-20-one, 13%, 2%, 2%; 3α-hydroxy-5α-pregnan-20-one, 3%, 3%, 6%; 20α-hydroxy-5α-pregnan-3-one, 0%, 2%, 3%; of radioactivity in muscle (free) and fat (free and conjugated fractions), respectively. Tentatively identified in fat extracts by chromatographic mobility were: 20α-hydroxy-4-pregnen-3-one, 1%, 1% and 3β-hydroxy-5β-pregnan-20-one, 0%, 2% of radioactivity in free and conjugated fractions, respectively. The average concentration of steroid in these animals due solely to treatment, calculated from the specific activity of the [¹⁴C] progesterone administered, was 3.4 and 18.1 ng/g in muscle and subcutaneous fat, respectively.     

Microbiological degradation of diazepam.

In studying the transformation of diazepam (7-chloro-1-methyl-5-phenyl-1,3-dihydro-2H-1,4-benzodiazepin-2-one) by fungi isolated from soil. N1-demethylation and cleavage of the diazepine ring were observed. Three metabolites: 7-chloro-5-phenyl-1,3-dihydro-2H-1,4-benzodiazepin-2-one, 2-acetamido-2"-benzoyl-4"-chloroacetanilide and 2-acetamido-2"-benzoyl-4"-chloro-N-methylacetanilide were isolated and identified.     

Metabolism of progesterone and testosterone by a Bacillus sp.

Microbial transformations by a Bacillus sp. were employed as a means of preparing potentially important derivatives of progesterone and testosterone. Each microbial metabolite was subjected to structure elucidation employing ¹H and ¹³C nmr, mass spectral and cd analysis. Hplc was used for the determination of the percentages of the metabolites formed. The progesterone metabolites were characterised as 14-hydroxy-4-pregnene-3,20-dione (II), 14-hydroxy-5 α -pregnane-3,6,20-trione (III)., 11 α — hydroxy-5 α — pregnane-3, 6,20-trione (IV) and 11 α, 14-dihydroxy-4-pregnene-3,20-dione (V). The testosterone analogs were identified as 4-androstene-3,17-dione (VII), 17 β-hydroxy-5 α -androstene-3,6-dione (VIII), 14-hydroxy-4-androstene-3,17-dione (IX) and 14, 17 β-dihydroxy-4-androsten -3-one (X)₁. The availability of the metabolites enabled complete elucidation of their ¹³C nmr spectra.