Synthesis of 3 beta,16 beta,19-trihydroxyandrost-5-en-17-one and 16 beta,19-dihydroxyandrost-4-ene-3,17-dione and their 19-oxo derivatives

3 beta,16 beta,19-Trihydroxyandrost-5-en-17-one (12) was synthesized from 5 alpha-bromo-3 beta-acetoxy-6 beta,19-epoxyandrostan-17-one (2) through acetoxylation at C-16 beta of the enol acetate 4 with lead tetraacetate and reductive cleavage of the epoxide ring with zinc dust yielding the 3 beta,16 beta-diacetoxy-19-hydroxy steroid 11, followed by hydrolysis of the acetoxy groups with sulfuric acid. Jones oxidation of compound 11 followed by the acid hydrolysis gave the 19-oxo steroid 15. 5 alpha-Bromo-3 beta-hydroxy-16 beta-acetoxy-6 beta,19-epoxyandrostan-17-one (8), obtained by selective hydrolysis of the 3-formate 5 with ammonium hydroxide, was oxidized with Jones reagent to afford the 3-oxo steroid 16, which was converted into the 19-hydroxy derivative 17 by treatment with zinc dust. 16 beta,19-Dihydroxyandrost-4-ene-3,17-dione (18) and its 19-oxo derivative 21 were obtained from compound 17 through a similar reaction sequence.     

Synthesis of 16 alpha,19-dihydroxy-4-androstene-3,17-dione and 3 beta,16 alpha,19-trihydroxy-5-androsten-17-one and their 17 beta-hydroxy-16-keto isomers

3 beta,16 alpha,19-Trihydroxy-5-androsten-17-one and 16 alpha,17-dihydroxy-4-androstene-3,17-dione were synthesized from the 5 alpha-bromo-6 beta,19-epoxy-17-ketone derivative 1, using the bromination at C-16 alpha of the 17-ketone 1 and the controlled alkaline hydrolysis of the 16 alpha-bromo-17-ketones 2 and 11 as key reactions. Zinc dust reductive cleavage of the 6 beta,19-epoxy-16 alpha-hydroxy-17-ketones 4 and 12, produced by controlled hydrolysis, gave the corresponding 19-alcohol derivatives 6 and 14, which were rearranged to the 17 beta-hydroxy-16-ketones 7 and 15 when treated with sodium hydroxide. The 3 beta,16 alpha,17 beta,19-tetrol 8 was obtained from the 16 alpha-ketol 6 by reaction with sodium borohydride.     

Reaction of thiol nucleophiles with 1,2-epoxy- and 4,5-epoxy-estrene-3-one-17 beta-ols

Four ring A steroidal epoxyenones as probable intermediate in the formation of catechol estrogens were synthesized. The isomeric 1 alpha,2 alpha-epoxy-17 beta-hydroxyestr-4-en-3-one (9) and 1 beta,2 beta-epoxy-17 beta-hydroxyestr-4-en-3-one (8) were synthesized from 17 beta-hydroxy-5 alpha-estra-3-one. The isomeric 4 alpha,5 alpha-epoxy-17 beta-hydroxyestr-1-en-3-one (11) and 4 beta,5 beta-epoxy-17 beta-hydroxyestr-1-en-3-one (10) were prepared from 19-nortestosterone. The reaction of 9 and 10 with sodium/ethanethiol resulted in the formation of three types of reactions leading to multiple products: 1,4-addition, opening of epoxide, and epoxide opening followed by dehydration. Reaction of 8 with ethanethiol gave only one compound identified as 2-ethanethio-1,4-estradien-17 beta-ol-3-one, while reaction of 9 with ethanethiol gave an unusual product identified as 4-estren-1 alpha,17 beta-diol-3-one. Unlike reaction of ethanethiol with 9 and 10, reaction with N-acetylecysteine or glutathione results in epoxide opening followed by dehydration leading to the formation of estradiol-4-thioethers.     

Synthesis of (25R)-26-hydroxy-15-ketosterols

(25R)-3beta,26-Dihydroxy-5alpha-cholest-8(14)-en-15-one (1) and (25R)-3beta,26-dihydroxy-5alpha,14beta-cholest-16-en-1 5-one (2) were synthesized from (25R)-3beta,26-dibenzoyloxy-5alpha,14alpha-chole st-16-ene (4). Oxidation of 4 with CrO3-3,5-dimethylpyrazole at -20 degrees C gave (25R)-3beta,26-dibenzoyloxy-5alpha,14alpha-chole st-16-en-15-one (5) along with (25R)-3beta,26-dibenzoyloxy-5alpha-cholest-16alpha+ ++,17alpha-epoxide (6). Oxidation of 5 with selenium dioxide afforded (25R)-3beta,26-dibenzoyloxy-5alpha-cholest-8(14),16-++ +dien-15-one (7) and (25R)-3beta,26-dibenzoyloxy-5alpha,14beta-choles t-16-en-15-one (8). Selective hydrogenation of 7 followed by hydrolysis in alcoholic potassium hydroxide yielded (25R)-3beta,26-dihydroxy-5alpha-cholest-8(14)-en-15-one (1). Hydrolysis of 5 and 8 in alcoholic potassium hydroxide provided (25R)-3beta,26-dihydroxy-5alpha,14beta-cholest-16-en-1 5-one (2).     

Chemical constituents of leaves and stem bark of Plumeria obtusa

The continued studies on the constituents of the fresh leaves and stem bark of Plumeria obtusa Linn. have led to the isolation and characterization of four new triterpenoids, dammara-12,20(22)Z-dien-3-one (1), dammara-12,20(22)Z-dien-3beta-ol (2), olean-12-en-3beta,27-diol (3), and 27-hydroxyolean-12-en-3-one (4) and 12 known compounds, which included eight triterpenoids; dammara-3beta,20(S),25-triol (5), urs-12-en-3beta-hydroxy-27-Z-feruloyloxy-28-oic acid (6), 3beta-hydroxyolean-12-en-28-oic acid (7), 3beta,27-dihydroxylupan-29-ene (8), 3beta-hydroxylupan-29-en-28-oic acid (9), 3beta-hydroxyursan-12-en-28-oic acid (11), 3beta-hydroxy-27-p-coumaroyloxy-olea-12-en-28-oic acid (12) and urs-12-en-3-one (15); an iridoid 1alpha-plumieride (10); a cardenolide 3alpha,14beta-dihydroxy-17beta-card-20(22)-enolide (13); a fatty acid ester methyl n-octadecanoate (14) and a steroid 3beta-hydroxy-delta5-stigmastane (16). The new constituents were characterized through spectroscopic studies including 1D (1H and 31C NMR) and 2D (COSY-45, NOESY, J-resolved, HMQC and HMBC) NMR and chemical transformations. This is the first report on the isolation of dammarane triterpenoids from P. obtusa. Compounds 5 and 6 are hitherto unreported from P. obtusa. The known compounds were identified by comparison of their spectral data with those reported in the literature.     

Investigation of the importance of the C-2 oxygen function in the transformation of stemodin analogues by Rhizopus oryzae ATCC 11145

A new stemodinoside, stemodin-alpha-L-arabinofuranoside (5), was isolated from the plant Stemodia maritima. Incubation of stemodin (2) with Rhizopus oryzae ATCC 11145 gave 2 alpha,7 beta,13(S)-trihydroxystemodane (17) and 2 alpha,3 beta,13(S),16 alpha-tetrahydroxystemodane (18) whilst stemodinone (8) afforded 6 alpha,13(S)-dihydroxystemodan-2-one (19). The bioconversion of 2 beta,13(S)-dihydroxystemodane (10) by the fungus yielded 2 beta,7 beta,13(S)-trihydroxystemodane (20) whereas stemod-12-en-2-one (9) provided 7 beta,17-dihydroxystemod-12-en-2-one (21). The results provide useful information about the relationship between the functional groups of the substrates and their potential for bioconversion.     

X-ray and deuterium labeling studies on the abnormal ring cleavages of a 5 beta-epoxide precursor of formestane

A new convergent synthesis of the antitumor steroid formestane (4-OHA) 5 has been performed from the easily available epimeric mixture of 5 alpha- and 5 beta-androst-3-en-17-one 1a and 1b in order to attempt a yield improvement. A two-step oxidative route followed by base-catalyzed isomerization was applied to the 5 alpha- and 5 beta-epimers 1a and 1b, either as a mixture or separately, leading to the title compound 5. From epimer 1a an efficient process was attained to prepare the desired aromatase inhibitor formestane. Epimer 1b led to the formation of the same compound 5. Additionally, 1b have also been converted in 5 beta-hydroxyandrostane-3,17-dione 12 and androst-4-ene-3,17-dione 13, revealing an unexpected reactivity of the 3 beta,4 beta-epoxy-5 beta-androstan-17-one intermediate 6 formed from 1b during the first oxidative step with performic acid. Cleavage of the epoxide 6 led to the trans-diaxial and the trans-diequatorial vic-diols 7 and 8 and to the 1,3-diol 9. The formation of the abnormal products 8 and 9 were investigated through X-ray and deuterium labeling studies. Diol 8 was formed through a trans-diequatorial epoxide ring opening and the 1,3-diol 9 was formed through an intramolecular rearrangement involving a 1,2-hydride shift. All the vic-diols 3, 7 and 8 formed, proved to be good precursors for the synthesis of the target compound 5.     

Inhibitors of sterol synthesis. Chemical synthesis and spectral properties of 3 beta-hydroxy-5 alpha-cholesta-8(14),24-dien-15-one, 3 beta,25-dihydroxy-5 alpha-cholest-8(14)-en-15-one, and 3 beta,24-dihydroxy-5 alpha-cholest-8(14)-en-15-one and their effects on 3-hydroxy-3-methylglutaryl coenzyme A reductase activity in CHO-K1 cells.

Side-chain functionalized delta 8(14)-15-ketosterols have been synthesized from 3 beta-acetoxy-24-hydroxy-5 alpha-chol-8(14)-en-15-one (VI) as part of a program to prepare potential metabolites and analogs of 3 beta-hydroxy-5 alpha-cholest-8(14)-en-15-one (I), a potent regulator of cholesterol metabolism. Oxidation of VI to the 24-aldehyde VII, followed by Wittig olefination with isopropyltriphenylphosphonium iodide gave 3 beta-acetoxy-5 alpha-cholesta-8(14),24-dien-15-one (VIII), which was hydrolyzed to the free sterol IX. Oxymercuration of VIII followed by hydrolysis of the 3 beta-acetate gave 3 beta,25-dihydroxy-5 alpha-cholest-8(14)-en-15-one (IV). Hydroboration-oxidation of VIII followed by hydrolysis of the 3 beta-acetate gave 3 beta,24-dihydroxy-5 alpha-cholest-8(14)-en-15-one (V) as a 5:4 mixture of the 24R and 24S epimers. 1H and 13C nuclear magnetic resonance (NMR) assignments and mass spectral fragmentation patterns, supported by high-resolution measurements, are presented for IV and its 3 beta-acetate, V, VII, VIII, and IX. Characterization of IV by NMR and of trimethylsilyl ethers of IV and V by gas chromatography-mass spectrometry was compatible with spectral data for samples of IV and V isolated previously after incubation of I with rat liver mitochondria in the presence of NADPH. Sterols IV, V, and IX were very potent in lowering of the level of 3-hydroxy-3-methylglutaryl coenzyme A reductase activity in Chinese hamster ovary cells; their potency was comparable to that of I.     

The chemistry of 9 alpha-hydroxysteroids. 1. Preparation of 9 alpha,17 beta-dihydroxy-17 alpha-ethynylandrost-4-en-3-one

9 alpha-Hydroxyandrost-4-ene-3,17-dione 1, when allowed to react with dipotassium acetylide in tetrahydrofuran, resulted, after chromatographic separation, in 4-methyl-19-norandrosta-4,9-diene-1,17-dione 2, 4 xi-methyl-19-norandrosta-5(10),9(11)-diene-1,17-dione 3, 4-methyl-17 alpha-ethynyl-17 beta-hydroxy-19-norandrosta-4,9-dien-1-one 4, 4 xi-methyl-17 alpha-ethynyl-17 beta-hydroxy-19-norandrosta-5(10),9(11)-dien- 1-one 5, and 17 alpha-ethynyl-17 beta-hydroxy-9,10-secoandrost-4-ene-3,9-dione 6. Selective protection of delta 4-3-ketone of 9 alpha-hydroxyandrost-4-ene-3,17-dione 1 as its dienol methyl ether 7, and subsequent reaction with lithium acetylide-ethylenediamine followed by acidic hydrolysis, afforded 9 alpha,17 beta-dihydroxy-17 alpha- ethynylandrost-4-en-3-one 8.     

Steroid hydroxylation by Whetzelinia sclerotiorum, Phanerochaete chrysosporium and Mucor plumbeus

The fungi Whetzelinia sclerotiorum ATCC 18687, Phanerochaete chrysosporium ATCC 24725 and Mucor plumbeus ATCC 4740 were examined for their ability to perform steroid biotransformations under single phase, pulse feed conditions. The steroids 3beta-hydroxyandrost-5-en-17-one (dehydroepiandrosterone) (1), 17beta-hydroxyandrost-4-en-3-one (testosterone) (5), 3beta-hydroxypregn-5-en-20-one (pregnenolone) (3), pregn-4-ene-3,20-dione (progesterone) (9), 17alpha,21-dihydroxypregn-4-ene-3,11,20-trione (cortisone) (11), 17alpha,21-dihydroxypregna-1,4-diene-3,11,20-trione (prednisone) (14), and 3-hydroxyestra-1,3,5(10)-trien-17-one (estrone) (15) were fed to each fungus. The production of a number of novel metabolites is reported. Of the fungi investigated W. sclerotiorum performed the most interesting biotransformations and had a clear propensity for 2beta, 6beta/7beta and 15beta/16beta hydroxylations. P. chrysosporium was more prone functionalize steroids in the allylic position. Oxygen insertion at C-14 by M. plumbeus is reported for the first time. All three micro-organisms exhibited redox activity.     

Synthesis of 4,19-disubstituted derivatives of DOC. Radioreceptor assay of some corticosteroid derivatives in human mononuclear leukocytes

Several new 4,19-substituted steroids and previously synthesized corticosteroids were assayed for affinity to type 1 receptors in human mononuclear leukocytes. 11 beta,19-epoxy-4,21-dihydroxypregn-4-ene-3,20-dione (2) was hydrogenated with Pd-C to yield a mixture of all four dihydro derivatives 5, accompanied by 4,21-diacetoxy-11 beta,19-epoxy-3-hydroxypregnan-20-one (6) and 21-acetoxy-11 beta,19-epoxy-4-hydroxypregnane-3,20-dione (7). With hot acetic + p-toluenesulfonic acid 5 underwent rearrangement to 21-acetoxy-11 beta,19-epoxypregn-5-ene-4,20-dione (8) Pd-C hydrogenation of 3,21-diacetoxy-5 beta,19-cyclopregna-2,9(11)-diene-4,20-dione (10) gave 3,21-diacetoxy-5 beta,19-cyclopregn-5-ene-4,20-dione (11) and the 9,11-dihydro derivative of the latter. Treatment of 10 with warm HCl furnished 19-chloro-4,21-dihydroxypregna-4,9(11)-diene-3,20-dione (13). Pd-C hydrogenation of its diacetate 14 afforded the 4,5-dihydro derivative 18, 19-chloro-21-acetoxypregn-9(11)-en-20-one (15), its 4-acetoxy derivative 16 and the 3,4-diacetoxy derivative 17. When tested in a radioreceptor assay in human mononuclear leukocytes the synthesized compounds showed only low relative binding affinities (RBA) to type 1 receptor, the highest being 0.72% for 13 (aldosterone = 100%). For comparison, other RBA in this system were: 19-noraldosterone, 20%; 18-deoxyaldosterone, 5.8%; 18-deoxy-19-noraldosterone, 4.7%; 18,21-anhydroaldosterone, 0.37%; 17-isoaldosterone, 7.6% and apoaldosterone, 4.3%     

Two oleanane triterpenoids from gordonia ceylanica and their conversions to taraxarane triterpenoids

Chemical investigation of the hot hexane extract of the stem bark of Gordonia ceylanica afforded two new oleanane triterpenoids, 3beta-acetoxy-11alpha, 13beta-dihydroxyolean-12-one and 3beta,11alpha-diacetoxy-13beta-hydroxyolean-12-one (2) The attempted acid hydrolysis of these two compounds resulted the dehydration and subsequent methyl group migration to afford the taraxarane triterpenoids 3beta,11alpha-dihydroxytaraxer-14-en-12-one (4) and 3beta-hydroxy-11alpha-acetoxytaraxer-14-en-12-one (5), respectively. These taraxaranes have not been previously reported.     

Microbial metabolism of steviol and steviol-16alpha,17-epoxide

Steviol (2) possesses a blood glucose-lowering property. In order to produce potentially more- or less-active, toxic, or inactive metabolites compared to steviol (2), its microbial metabolism was investigated. Incubation of 2 with the microorganisms Bacillus megaterium ATCC 14581, Mucor recurvatus MR 36, and Aspergillus niger BCRC 32720 yielded one new metabolite, ent-7alpha,11beta,13-trihydroxykaur-16-en-19-oic acid (7), together with four known related biotransformation products, ent-7alpha,13-dihydroxykaur-16-en-19-oic acid (3), ent-13-hydroxykaur-16-en-19-alpha-d-glucopyranosyl ester (4), ent-13,16beta,17-trihydroxykauran-19-oic acid (5), and ent-13-hydroxy-7-ketokaur-16-en-19-oic acid (6). The preliminary testing of antihyperglycemic effects showed that 5 was more potent than the parent compound (2). Thus, the microbial metabolism of steviol-16alpha,17-epoxide (8) with M. recurvatus MR 36 was continued to produce higher amounts of 5 for future study of its action mechanism. Preparative-scale fermentation of 8 yielded 5, ent-11alpha,13,16alpha,17-tetrahydroxykauran-19-oic acid (10), ent-1beta,17-dihydroxy-16-ketobeyeran-19-oic acid (11), and ent-7alpha,17-dihydroxy-16-ketobeyeran-19-oic acid (13), together with three new metabolites: ent-13,16beta-dihydroxykauran-17-acetoxy-19-oic acid (9), ent-11beta,13-dihydroxy-16beta,17-epoxykauran-19-oic acid (12), and ent-11beta,13,16beta,17-tetrahydroxykauran-19-oic acid (14). The structures of the compounds were fully elucidated using 1D and 2D NMR spectroscopic techniques, as well as HRFABMS. In addition, a GRE (glucocorticoid responsive element)-mediated luciferase reporter assay was used to initially screen the compounds 3-5, and 7 as glucocorticoid agonists. Compounds 4, 5 and 7 showed significant effects.     

The effect of 4beta and 19 ester functionalities on some electrophilic addition reactions of delta5-steroids

The reactions of 3beta-acyloxyandrost-5-enes with bromine/silver acetate (Petrow reaction) and mercury(II) trifluoroacetate (modified Treibs oxidation) have been used previously to effect allylic oxidation on these substrates en route to biologically active compounds. In both these reactions, which involve electrophilic addition to the delta5-bond, the 3-acyloxy substituent plays a significant role. In this report, the effect of introducing other substituents proximate to the delta5-bond has been studied by using derivatives of 3beta-acetoxyandrost-5-en-17-one (1), namely, 3beta,4beta-diacetoxyandrost-5-en-17-one (13), 3beta,19-diacetoxyandrost-5-en-17-one (14), 3beta-acetoxyandrost-5-ene-7,17-dione (15), and 3beta-acetoxy-4,4-dimethylandrost-5-en-17-one (17). Our results indicate that in both sets of reactions the effect of the introduced functional groups was pronounced. In the Petrow reaction, electrophilic addition rather than allylic oxidation on the diacetates was observed. With the Treibs reaction, allylic oxidation on the diacetates occurred. The 7-keto and 4,4-dimethyl steroids proved to be poor substrates in both reactions.     

Biotransformation of cadinane sesquiterpenes by Beauveria bassiana ATCC 7159

Incubation of cadina-4,10(15)-dien-3-one with Beauveria bassiana ATCC 7159 has resulted in the production of nine novel sesquiterpenes. These metabolites were identified as (4S)-cadin-10(15)-en-3-one, (4S)-3 alpha-hydroxycadin-10(15)-ene, (4R)-3 alpha-hydroxycadin-10(15)-ene, (4S)-3 beta-hydroxycadin-10(15)-ene, (4S)-3 beta-hydroxycadina-10(15),12(14)-diene, (4S)-13-hydroxycadin-10(15)-en-3-one, (4S)-12-hydroxycadin-10(15)-en-3-one, (4R)-3 beta, 14-dihydroxycadin-10(15)-ene and 3 alpha-hydroxycadina-4,10(15)-diene. The allylic alcohol 3 alpha-hydroxycadina-4,10(15)-diene was also biotransformed to afford cadina-4,10(15)-dien-3-one, (4S)-cadin-10(15)-en-3-one and (4S)-12-hydroxycadin-10(15)-en-3-one. The insecticidal potential and phytotoxicity of the isolated metabolites have been evaluated.     

Antimalarial constituents from Nauclea orientalis (L.) L

Bioassay-guided fractionation of the antimalarial-active CHCl3 extract of the dried stem of Nauclea orientalis (L.) L. (Rubiaceae) has resulted in the isolation of two novel tetrahydro-beta-carboline monoterpene alkaloid glucosides, naucleaorine (= (16alpha,17beta)-3,14:15,20-tetradehydro-16-ethenyl-17-(beta-D-glucopyranosyloxy)-19alpha-methoxyoxayohimban-21-one; 1) and epimethoxynaucleaorine (2), as well as the known compounds, strictosidine lactam (= (15beta,16alpha,17beta)-19,20-didehydro-16-ethenyl-17-(beta-D-glucopyranosyloxy)oxayohimban-21-one; 3), 3,4,5-trimethoxyphenol (4), 3alpha-hydroxyurs-12-en-28-oic acid methyl ester (5), 3alpha,23-dihydroxyurs-12-en-28-oic acid (6), 3alpha,19alpha,23-trihydroxyurs-12-en-28-oic acid methyl ester (7), and oleanolic acid (8). Compounds 1, 2, 6, and 8 showed moderate in vitro activities against Plasmodium falciparum. Their structures and configurations were elucidated by spectroscopic methods including 1D- and 2D-NMR analyses.     

Comparative Studies on Microbial and Chemical Modifications of Trichothecene Mycotoxins

The microbial modification of several trichothecene mycotoxins by trichothecene-producing strains of Fusarium nivale and F. solani was studied. These results were compared with the corresponding chemical modifications. The growing mycelia of Fusarium spp. did not convert 4beta-acetoxy-3alpha,7alpha, 15-trihydroxy-12, 13-epoxytrichothec-9-en-8-one (fusarenon) into 3alpha,4beta, 7alpha,15-tetrahydroxy-12,13-epoxy-trichothec-9-en-8-one (nivalenol), whereas 3alpha,4beta,7alpha,15-tetracetoxy-12,13-epoxytrichothec-9-en-8-one (tetraacetylnivalenol) was deacetylated to yield 3alpha-hydroxy-4beta,7alpha,15-triacetoxy-12,13-epoxytrichothec-9-en-8-one (4,7,15-triae-tylnivalenol), which was resistant to further deacetylation. T-2 toxin was transformed intoHT-2 toxin, and 8alpha-(3-methylbutyryloxy)-3alpha,4beta,-15-triacetoxy-12,13-epoxytrichothec-9-en-8-one (T-2 acetate) was transformed into HT-2 toxin via T-2 toxin. Chemical modification with ammonium hydroxide converted tetraacetylnivalenol into fusarenon via 4,7,15-triacetylnivalenol. 3alpha-7alpha,15-Triacetoxy-12,13-epoxytrichothec-9-en-8-one (triacetyldeoxynivalenol) gave deacetylation products lacking the C-7 or c-15 acetyl group in addition to 7alpha,15- diacetoxy-3alpha-hydroxy-12, 13-epoxytrichothec-9-en-8-one (7,15-diacetyldeoxynivalenol). These results demonstrate the regio-selectivity in microbial modification of trichothecenes. Based on the results and available knowledge concerning the transformation of trichothecenes, mechanisms for biological modifications of these mycotoxins are postulated.     

Diterpenoids from the pericarp of Platycladus orientalis

Eight labdane-type diterpenes, 7beta,13S-dihydroxylabda-8(17),14-dien-19-oic acid (1), 12R,15-dihydroxylabda-8(17),13E-dien-19-oic acid (3c), 12R,15-dihydroxylabda-8(17),13Z-dien-19-oic acid (3d), 12R,13R,14S-trihydroxylabda-12,15-epoxy-8(17)-en-19-oic acid (4a), 12S,13S,14R-trihydroxylabda-12,15-epoxy-8(17)-en-19-oic acid (4b), 15-hydroxy-12-oxolabda-8(17),13E-dien-19-oic acid (5), 14R,15-dihydroxylabda-8(17),12Z-dien-19-oic acid (7a) and 14S,15-dihydroxylabda-8(17),12Z-dien-19-oic acid (7b), along with 20 known diterpenoids, were isolated from the pericarp of Platycladus orientalis. Their structures were unambiguously elucidated by NMR spectroscopic and single crystal X-ray diffraction analyses, as well as via chemical correlation conversion. NMR spectroscopic data of known isomers 8c and 8d were reported as a supplement to existing data.     

Ent-kauren-19-oic acid derivatives from the stem bark of Croton pseudopulchellus Pax

Two new ent-kauren-19-oic acid derivatives, ent-14S*-hydroxykaur-16-en-19-oic acid and ent-14S*,17-dihydroxykaur-15-en-19-oic acid together with eleven known compounds ent-kaur-16-en-19-oic acid, ent-kaur-16-en-19-al, ent-12β-hydroxykaur-16-en-19-oic acid, ent-12β-acetoxykaur-16-en-19-oic acid, 8R,13R-epoxylabd-14-ene, eudesm-4(15)-ene-1β,6α-diol, (?)-7-epivaleran-4-one, germacra-4(15), 5E,10(14)-trien-9β-ol, acetyl aleuritolic acid, β-amyrin, and stigmasterol were isolated from the stem bark of Croton pseudopulchellus (Euphorbiaceae). Structures were determined using spectroscopic techniques. Ent-14S*-hydroxykaur-16-en-19-oic acid, ent-kaur-16-en-19-oic acid, ent-12β-hydroxykaur-16-en-19-oic acid, ent-12β-acetoxykaur-16-en-19-oic acid and 8R,13R-epoxylabd-14-ene were tested for their effects on Semliki Forest virus replication and for cytotoxicity against human liver tumour cells (Huh-7 strain) but were found to be inactive. Ent-kaur-16-en-19-oic acid, the major constituent, showed weak activity against the Plasmodium falciparum (CQS) D10 strain.     

Detection and mass spectrometric characterization of novel long-term dehydrochloromethyltestosterone metabolites in human urine

The biotransformation of dehydrochloromethyltestosterone (DHCMT, 4-chloro-17β-hydroxy,17α-methylandrosta-1,4-dien-3-one) in man was studied with the aim to discover long-term metabolites valuable for the antidoping analysis. Having applied a high performance liquid chromatography for the fractionation of urinary extract obtained from the pool of several DHCMT positive urines, about 50 metabolites were found. Most of these metabolites were included in the GC-MS/MS screening method, which was subsequently applied to analyze the post-administration and routine doping control samples. As a result of this study, 6 new long-term metabolites were identified tentatively characterized using GC-MS and GC-MS/MS as 4-chloro-17α-methyl-5β-androstan-3α,16,17β-triol (M1), 4-chloro-18-nor-17β-hydroxymethyl,17α-methyl-5β-androsta-1,13-dien-3α-ol (M2), 4-chloro-18-nor-17β-hydroxymethyl,17α-methyl-5β-androst-13-en-3α-ol (M3), its epimer 4-chloro-18-nor-17α-hydroxymethyl,17β-methyl-5β-androst-13-en-3α-ol, 4-chloro-18-nor-17β-hydroxymethyl,17α-methylandrosta-4,13-dien-3α-ol (M4) and its epimer 4-chloro-18-nor-17α-hydroxymethyl,17β-methylandrosta-4,13-dien-3α-ol. The most long-term metabolite M3 was shown to be superior in the majority of cases to the other known DHCMT metabolites, such as 4-chloro-18-nor-17β-hydroxymethyl,17α-methylandrosta-1,4,13-trien-3-one and 4-chloro-3α,6β,17β-trihydroxy-17α-methyl-5β-androst-1-en-16-one.