Comparison of sulfo‐conjugated and gluco‐conjugated urinary metabolites for detection of methenolone misuse in doping control by LC‐HRMS,GC‐MS and GC‐HRMS

Methenolone (17β‐hydroxy‐1‐methyl‐5α‐androst‐1‐en‐3‐one) misuse in doping control is commonly detected by monitoring the parent molecule and its metabolite (1‐methylene‐5α‐androstan‐3α‐ol‐17‐one) excreted conjugated with glucuronic acid using gas chromatography‐mass spectrometry (GC‐MS) and liquid chromatography mass spectrometry (LC‐MS) for the parent molecule, after hydrolysis with β‐glucuronidase. The aim of the present study was the evaluation of the sulfate fraction of methenolone metabolism by LC‐high resolution (HR)MS and the estimation of the long‐term detectability of its sulfate metabolites analyzed by liquid chromatography tandem mass spectrometry (LC‐HRMSMS) compared with the current practice for the detection of methenolone misuse used by the anti‐doping laboratories. Methenolone was administered to two healthy male volunteers, and urine samples were collected up to 12 and 26 days, respectively. Ethyl acetate extraction at weak alkaline pH was performed and then the sulfate conjugates were analyzed by LC‐HRMS using electrospray ionization in negative mode searching for [M‐H]^? ions corresponding to potential sulfate structures (comprising structure alterations such as hydroxylations, oxidations, reductions and combinations of them). Eight sulfate metabolites were finally detected, but four of them were considered important as the most abundant and long term detectable. LC clean up followed by solvolysis and GC/MS analysis of trimethylsilylated (TMS) derivatives reveal that the sulfate analogs of methenolone as well as of 1‐methylene‐5α‐androstan‐3α‐ol‐17‐one, 3z‐hydroxy‐1β‐methyl‐5α‐androstan‐17‐one and 16β‐hydroxy‐1‐methyl‐5α‐androst‐1‐ene‐3,17‐dione were the major metabolites in the sulfate fraction. The results of the present study also document for the first time the methenolone sulfate as well as the 3z‐hydroxy‐1β‐methyl‐5α‐androstan‐17‐one sulfate as metabolites of methenolone in human urine. The time window for the detectability of methenolone sulfate metabolites by LC‐HRMS is comparable with that of their hydrolyzed glucuronide analogs analyzed by GC‐MS. The results of the study demonstrate the importance of sulfation as a phase II metabolic pathway for methenolone metabolism, proposing four metabolites as significant components of the sulfate fraction. Copyright © 2015 John Wiley & Sons, Ltd.     

Four New Pregnane Steroids from Aglaia abbreviata and Their Cytotoxic Activities

Four new pregnane steroids, aglaiasterols A–D ( 1 – 4 ), have been isolated from the EtOH extract of stems of Aglaia abbreviata. They were identified as (3α,5α,17Z)‐3‐hydroxypregn‐17‐en‐16‐one ( 1 ), (3β,5α,17E)‐3‐hydroxypregn‐17‐en‐16‐one ( 2 ), (3β,5α,17Z)‐3‐hydroxypregn‐17‐en‐16‐one ( 3 ), and (3α,5α,20S*)‐3‐hydroxy‐16‐oxopregnan‐20‐yl acetate ( 4 ) on the basis of spectroscopic methods, including 1D‐ and 2D‐NMR techniques. Compounds 1 – 4 were evaluated for their cytotoxic activities against K562 (human leukemia), MCF‐7 (human breast cancer), and KB (human oral epithelium cancer) cells, and drug‐resistant cells of K562/A02, MCF‐7/ADM, and KB/VCR. These isolates showed weak to moderate inhibitory effects on the growth of the tested cell lines.     

Photooxygenation of Pregnanes

The course of the singlet‐oxygen reaction with pregn‐17(20)‐enes and pregn‐5,17(20)‐dienes was studied to compare the reactivity of the two alkene moieties present in some steroid families. Thus, from commercially available (3β,5α)‐hydroxy‐androstan‐17‐one and (3β)‐3‐hydroxyandrost‐5‐en‐17‐one, the following 3‐{[(tert‐butyl)dimethylsilyl]oxy}‐substituted, 17(20)‐unsaturated pregnanes were prepared (see Fig. 1): (3β,5α)‐21‐norpregn‐17(20)‐ene 1 ; (3β,5α,17Z)‐pregn‐17(20)‐ene 2 , (3β,5α,16α,17E)‐pregn‐17(20)‐en‐16‐ol 3 , (16β,5α,17E)‐pregn‐17(20)‐en‐16‐ol 4 , (3β,5α,16β,17E)‐pregn‐17(20)‐en‐16‐ol acetate 5 , (3β,16α)‐21‐norpregna‐5,17(20)‐dien‐16‐ol 6 , (3β,16α,17E)‐pregna‐5,17(20)‐dien‐16‐ol 7 , (3β,17Z)‐pregna‐5,17(20)‐diene 8 , (3β,17E)‐pregna‐5,17(20)‐dien‐21‐ol 9 and (3β,17E)‐5,17(20)‐dien‐21‐ol acetate 10 . The oxygenated products (see Fig. 2) obtained from 1 – 10 and ¹O₂, generated by irradiation of Rose Bengal in ³O₂‐saturated pyridine solution, were characterized by ¹H‐, ¹³C‐NMR, and MS (EI, FAB, HR‐EI, ESI‐ and UV‐MALDI‐TOF) data. Major products were those formed by the ene reaction involving as intermediates the corresponding hydroperoxides and the cyclic tautomers of the allylic hydroperoxides, i.e., the corresponding oxiranium oxide‐like intermediate (Scheme 5).     

Triterpenoid Saponins from the Spikes of Prunella vulgaris

Three new oleanane‐skeleton triterpenoid saponins, 3β,4β,16α‐17‐carboxy‐16,24‐dihydroxy‐28‐norolean‐12‐en‐3‐yl 4‐O‐β‐D ‐xylopyranosyl‐β‐D ‐glucopyranosiduronic acid ( 1 ), (3β,4β,16α)‐17‐carboxy‐16,24‐dihydroxy‐28‐norolean‐12‐en‐3‐yl β‐D ‐glucopyranosiduronic acid methyl ester ( 2 ), and (3β,4β)‐24‐hydroxy‐16‐oxo‐28‐norolean‐12‐en‐3‐yl 4‐O‐β‐D ‐xylopyranosyl‐β‐D ‐glucopyranosiduronic acid ( 3 ), together with eight known constituents, i.e., the oleanane‐type triterpenoids 4 – 6 , and the ursane‐type triterpenoids 7 – 11 , were isolated from the spikes of Prunella vulgaris. The new structures were established by means of detailed spectroscopic analysis (IR, HR‐ESI‐MS, 1D‐ and 2D‐NMR experiments). Compounds 1 – 3 were tested for their inhibition activity against the growth of tumor cell lines; only compound 3 displayed marginal inhibition activity.     

Chemical Constituents from Fruits and Stem Bark of Celtis australis L.

Four triterpenoids named (9β,31R)‐9,25‐cyclo‐30‐propylhopan‐31‐ol ( 1 ), (3β)‐3‐hydroxy‐30‐propylhopan‐31‐one ( 2 ), (3β)‐oleanan‐3‐ol ( 3 ), and (3β,9β)‐9,25‐cycloolean‐12‐en‐3‐yl β‐D ‐glucofuranoside ( 4 ), a steroid named (3β,9β,14β)‐14‐hydroxy‐9,19‐cyclocholan‐3‐yl β‐D ‐glucopyranoside ( 5 ), and an anthraquinone named 6‐hydroxy‐5,7,8‐trimethoxy‐9,10‐dioxo‐9,10‐dihydroanthracen‐2‐yl acetate ( 6 ) have been isolated from the fruits and bark of Celtis australis (Ulmaceae), along with apigenin, quercetin, and its glucoside. Their structures were elucidated by means of chemical and spectral analysis including COSY, NOESY, and HMBC experiments.     

Diterpenes from Xylopia langsdorffiana

The phytochemical investigation of Xylopia langsdorffiana A.St.‐Hil. & Tul . led to the isolation of eight diterpenes, i.e., of the four new compounds (5β,7β,8α,9β,10α,12α)‐atisane‐7,16‐diol 7‐acetate ( 1 ), named xylodiol 7‐acetate, (5β,8α,9β,10α,12α)‐16‐hydroxyatisan‐7‐one ( 2 ), named xylopinone, (3α,12Z)‐3‐hydroxy‐ent‐labda‐8(20),12,14‐trien‐18‐oic acid ( 3 ), named labdorffianic acid A, and 8,20‐epoxy‐13‐hydroxy‐ent‐labd‐14‐en‐18‐oic acid ( 4 ), named labdorffianic acid B, and of the four known compounds 5 – 8 , i.e., ent‐kauran‐16‐ol, ent‐kaur‐16‐en‐19‐oic acid, ent‐kaur‐16‐en‐19‐ol, and ent‐trachyloban‐18‐oic acid. The structures were established by IR, HR‐ESI‐MS, and NMR data analysis with the aid of 2D techniques.     

New potential biomarkers for mesterolone misuse in human urine by liquid chromatography quadrupole time‐of‐flight mass spectrometry

In this paper, mesterolone metabolic profiles were investigated carefully. Mesterolone was administered to one healthy male volunteer. Urinary extracts were analyzed by liquid chromatography quadruple time‐of‐flight mass spectrometry (LC‐QTOFMS) for the first time. Liquid–liquid extraction was applied to processing urine samples, and dilute‐shoot analyses of intact metabolites were also presented. In LC‐QTOFMS analysis, chromatographic peaks for potential metabolites were hunt down by using the theoretical [M–H]^? as target ions in full scan experiment, and their actual deprotonated ions were analyzed in targeted MS/MS mode. Ten metabolites including seven new sulfate and three glucuronide conjugates were found for mesterolone. Because of no useful fragment ion for structural elucidation, gas chromatography–mass spectrometry instrumentation was employed to obtain structural details of the trimethylsilylated phase I metabolite released after solvolysis. Thus, their potential structures were proposed particularly by a combined MS approach. All the metabolites were also evaluated in terms of how long they could be detected, and S1 (1α‐methyl‐5α‐androst‐3‐one‐17β‐sulfate) together with S2 (1α‐methyl‐5α‐androst‐17‐one‐3β‐sulfate) was detected up to 9 days after oral administration, which could be the new potential biomarkers for mesterolone misuse. Copyright © 2015 John Wiley & Sons, Ltd.     

In vitro and in vivo studies of androst‐4‐ene‐3,6,17‐trione in horses by gas chromatography–mass spectrometry

This paper describes the application of gas chromatography–mass spectrometry (GC‐MS) for in vitro and in vivo studies of 6‐OXO in horses, with a special aim to identify the most appropriate target metabolite to be monitored for controlling the administration of 6‐OXO in racehorses. In vitro studies of 6‐OXO were performed using horse liver microsomes. The major biotransformation observed was reduction of one keto group at the C3 or C6 positions. Three in vitro metabolites, namely 6α‐hydroxyandrost‐4‐ene‐3,17‐dione (M1), 3α‐hydroxyandrost‐4‐ene‐6,17‐dione (M2a) and 3β‐hydroxyandrost‐4‐ene‐6,17‐dione (M2b) were identified. For the in vivo studies, two thoroughbred geldings were each administered orally with 500 mg of androst‐4‐ene‐3,6,17‐trione (5 capsules of 6‐OXO_®) by stomach tubing. The results revealed that 6‐OXO was extensively metabolized. The three in vitro metabolites (M1, M2a and M2b) identified earlier were all detected in post‐administration urine samples. In addition, seven other urinary metabolites, derived from a further reduction of either one of the remaining keto groups or one of the remaining keto groups and the olefin group, were identified. These metabolites included 6α,17β‐dihydroxyandrost‐4‐en‐3‐one (M3a), 6,17‐dihydroxyandrost‐4‐en‐3‐one (M3b and M3c), 3β,6β‐dihydroxyandrost‐4‐en‐17‐one (M4a), 3,6‐dihydroxyandrost‐4‐en‐17‐one (M4b), 3,6‐dihydroxyandrostan‐17‐one (M5) and 3,17‐dihydroxyandrostan‐6‐one (M6). The longest detection time observed in urine was up to 46 h for the M6 metabolite. For blood samples, the peak 6‐OXO plasma concentration was observed 1 h post administration. Plasma 6‐OXO decreased rapidly and was not detectable 12 h post administration. Copyright © 2009 John Wiley & Sons, Ltd.     

New Furostanol Glycosides from the Roots of Digitalis ciliata Trautv.

Three new furostanol glycosides, named ciliatasides A, B, and C ( 1 – 3 , resp.), have been isolated from the roots of Digitalis ciliata, along with two known furostanol glycosides. The structures of the new compounds were identified as (2α,3β,5α,14β,25R)‐26‐(β‐D ‐glucopyranosyloxy)‐2‐hydroxyfurost‐20(22)‐en‐3‐yl β‐D ‐glucopyranosyl‐(1→2)‐[β‐D ‐glucopyranosyl‐(1→3)]‐β‐D ‐galactopyranoside ( 1 ), (2α,3β,5α,14β,22R)‐26‐(β‐D ‐glucopyranosyloxy)‐2‐hydroxy‐22‐methoxyfurost‐25(27)‐en‐3‐yl β‐D ‐galactopyranosyl‐(1→2)‐[β‐D ‐xylopyranosyl‐(1→3)]‐β‐D ‐glucopyranosyl‐(1→4)‐β‐D ‐galactopyranoside ( 2 ), and (2α,3β,5α,14β,22R,25R)‐26‐(β‐D ‐glucopyranosyloxy)‐2,22‐dihydroxyfurostan‐3‐yl β‐D ‐glucopyranosyl‐(1→2)‐[β‐D ‐glucopyranosyl‐(1→3)]‐β‐D ‐galactopyranoside ( 3 ).     

Triterpene Esters Isolated from Leaves of Maytenus salicifolia Reissek

The triterpene ester (3β)‐olean‐18‐en‐3‐yl stearate ( 1 ), together with (3β)‐urs‐12‐en‐3‐yl stearate ( 2 ), and (3β)‐lup‐20(29)‐en‐3‐yl stearate ( 3 ) were isolated from leaves of Maytenus salicifolia Reissek (Celastraceae). The structure of 1 , a new compound, including its configuration, was established by ¹H, ¹³C, and DEPT‐135 NMR data, including 2D experiments (HSQC, HMBC, COSY, and NOESY). The molecular mass (692 Da) was confirmed by gas chromatography coupled with mass spectrometry (CG/MS).     

Palmitoleate (=(9Z)‐Hexadeca‐9‐enoate) Esters of Oleanane Triterpenoids from the Golden Flowers of Tagetes erecta: Isolation and Autoxidation Products

Six oleanane‐type triterpenoid esters were isolated from the golden flowers of Tagetes erecta. Spectral studies characterized their structures as 3‐O‐[(9Z)‐hexadec‐9‐enoyl]erythrodiol ( 1 ), 11α,12α:13β,28‐diepoxyoleanan‐3β‐yl (9Z)‐hexadec‐9‐enoate ( 2 ), 13β,28‐epoxyolean‐11‐en‐3β‐yl (9Z)‐hexadec‐9‐enoate ( 3 ), 28‐hydroxy‐11‐oxoolean‐12‐en‐3β‐yl (9Z)‐hexadec‐9‐enoate ( 4 ), 3‐O‐[(9Z‐hexadec‐9‐enoyl]‐β‐amyrin ( 5 ), and 11‐oxoolean‐12‐en‐3β‐yl (9Z)‐hexadec‐9‐enoate ( 6 ). Compounds 1 – 4 and 6 are new natural products, while the known 5 was isolated for the first time from the genus Tagetes, from which only one triterpenoid has earlier been obtained. Aerial oxidation (autoxidation) converted amyrin 1 into 2 – 4 and transformed amyrin 5 into 6 . The configuration of 1 – 6 and an autoxidation mechanism (Scheme) involving the formation of the intermediate 11α‐hydroxyolean‐12‐ene derivatives 1b and 5b on thermal decomposition of the labile 11α‐OOH derivatives 1a and 5a , respectively, under neutral conditions are discussed. For the first time, the reactivity of the allylic H? C(11) bond of triterpenoids of type 1 and 5 toward aerial oxidation was observed. The long‐chain ester group at C(3) of 1 and 5 may be responsible for their labile nature, as β‐amyrin ( 7 ), erythrodiol ( 8 ), and ursolic acid were found to be inert toward autoxidation.     

Foetidissimosides C–F,Novel Glycosides from the Roots of Cucurbita foetidissima

Two novel echinocystic acid (=(3β,16α)‐3,16‐dihydroxyolean‐12‐en‐28‐oic acid) glycosides, foetidissimosides C ( 1 ), and D ( 2 ), along with new cucurbitane glycosides, i.e., foetidissimosides E/F ( 3 / 4 ) as an 1 : 1 mixture of the (24R)/(24S) epimers, were obtained from the roots of Cucurbita foetidissima. Their structures were elucidated by means of a combination of homo‐ and heteronuclear 2D‐NMR techniques (COSY, TOCSY, NOESY, ROESY, HSQC, and HMBC), and by FAB‐MS. The new compounds were characterized as (3β,16α)‐28‐{[O‐β‐D ‐glucopyranosyl‐(1→3)‐O‐β‐D ‐xylopyranosyl‐(1→4)‐O‐6‐deoxy‐α‐L ‐mannopyranosyl‐(1→2)‐α‐L ‐arabinopyranosyl]oxy}‐16‐hydroxy‐28‐oxoolean ‐12‐en‐3‐yl β‐D ‐glucopyranosiduronic acid ( 1 ), (3β,16α)‐16‐hydroxy‐28‐oxo‐28‐{{O‐β‐D ‐xylopyranosyl‐(1→3)‐O‐[β‐D ‐xylopyranosyl‐(1→4)]‐O‐6‐deoxy‐α‐L ‐mannopyranosyl‐(1→2)‐α‐L ‐arabinopyranosyl}oxy}olean‐12‐en‐3‐yl β‐D ‐glucopyranosiduronic acid ( 2 ), and (3β,9β,10α,11α,24R)‐ and (3β,9β,10α,11α,24S)‐25‐(β‐D ‐glucopyranosyloxy)‐9‐methyl‐19‐norlanost‐5‐en‐3‐yl 2‐O‐β‐D ‐glucopyranosyl‐β‐D ‐glucopyranoside ( 3 and 4 , resp.).     

Triumfettosterol Id and Triumfettosaponin,a New (Fatty Acyl)‐Substituted Steroid and a Triterpenoid ‘Dimer’ Bis(β‐D‐glucopyranosyl) Ester from the Leaves of Wild Triumfetta cordifolia A. Rich. (Tiliaceae)

Two new triterpenoid derivatives were isolated from the leaves of wild Triumfetta cordifolia A. Rich . and identified to be a (fatty acyl)‐substituted steroid 1 and a triterpenoid saponin ‘dimer’ 2 , named (3β)‐stigmasta‐5,22‐diene‐3,29‐diol 3‐propanoate 29‐triacontanoate and (2α,3β,19α)‐2,3,19‐trimethoxyurs‐12‐ene‐24,28‐dioic acid 24‐[(2α,3β)‐24,28‐bis(β‐D ‐glucopyranosyloxy)‐2‐hydroxy‐24,28‐dioxours‐12‐en‐3‐yl] ester, respectively. These compounds were obtained together with a mixture of known sterols (stigmasterol/β‐sitosterol=(3β,22E)‐stigmasta‐5,22‐dien‐3‐ol/(3β)‐stigmast‐5‐en‐3‐ol) and trans‐tiliroside ( 3 ). The structures 1 and 2 were determined on the basis of NMR data (¹H‐, ¹³C‐, and 2D‐NMR analyses) and mass spectrometry and confirmed by chemical transformations. The antimicrobial activities of trans‐tiliroside ( 3 ) against eight bacterial and two fungal strains were evaluated. This compound showed weak activities on some bacterial strains.     

Three New Phthalides from Gnaphalium adnatum

Three new phthalides, gnaphalides A–C ( 1 – 3 , resp.), together with three known phthalides, were isolated from the aerial part of Gnaphalium adnatum. The structures of the new compounds were elucidated as 6‐(1,1‐dimethylprop‐2‐en‐1‐yl)‐5,7‐dihydroxy‐2‐benzofuran‐1(3H)‐one ( 1 ), 5‐hydroxy‐7‐[(2‐hydroxy‐3‐methylbut‐3‐en‐1‐yl)oxy]‐2‐benzofuran‐1(3H)‐one ( 2 ), and 1,3‐dihydro‐7‐[(3‐methylbut‐2‐en‐1‐yl)oxy]‐1‐oxo‐2‐benzofuran‐5‐yl β‐D ‐glucopyranoside ( 3 ) on the basis of spectral analyses. The structure of 1 was also confirmed by X‐ray crystallographic analysis. The three known phthalides, identified as 5,7‐dihydroxyisobenzofuran‐1(3H)‐one ( 4 ), anaphatol ( 5 ), and 7‐O‐(β‐glucopyranosyl)‐5‐hydroxyisobenzofuran‐1(3H)‐one ( 6 ), were isolated from the genus Gnaphalium for the first time.     

Metabolism of androsta‐1,4,6‐triene‐3,17‐dione and detection by gas chromatography/mass spectrometry in doping control

The urinary metabolism of the irreversible aromatase inhibitor androsta‐1,4,6‐triene‐3,17‐dione was investigated. It is mainly excreted unchanged and as its 17β‐hydroxy analogue. For confirmation, 17β‐hydroxyandrosta‐1,4,6‐trien‐3‐one was synthesized and characterized by nuclear magnetic resonance (NMR) in addition to the parent compound. In addition, several reduced metabolites were detected in the post‐administration urines, namely 17β‐hydroxyandrosta‐1,4‐dien‐3‐one (boldenone), 17β‐hydroxy‐5β‐androst‐1‐en‐3‐one (boldenone metabolite), 17β‐hydroxyandrosta‐4,6‐dien‐3‐one, and androsta‐4,6‐diene‐3,17‐dione. The identification was performed by comparison of the metabolites with reference material utilizing gas chromatography/mass spectrometry (GC/MS) of the underivatized compounds and GC/MS and GC/tandem mass spectrometry (MS/MS) of their trimethylsilyl (TMS) derivatives. Alterations in the steroid profile were also observed, most obviously in the androsterone/testosterone ratio. Even if not explicitly listed, androsta‐1,4,6‐triene‐3,17‐dione is classified as a prohibited substance in sports by the World Anti‐Doping Agency (WADA) due to its aromatase‐inhibiting properties. In 2006 three samples from human routine sports doping control tested positive for metabolites of androsta‐1,4,6‐triene‐3,17‐dione. The samples were initially found suspicious for the boldenone metabolite 17β‐hydroxy‐5β‐androst‐1‐en‐3‐one. Since metabolites of androst‐4‐ene‐3,6,17‐trione were also present in the urine samples, it is presumed that these findings were due to the administration of a product like ‘Novedex Xtreme’, which could be easily obtained from the sport supplement market. Copyright © 2008 John Wiley & Sons, Ltd.     

A new Sequiterpenoid from Eupatorium adenophorum Spreng

A new sequiterpenoid compound 8aα-hydroxy-1-isopropyl-4,7-dimethyl-1,2,3,4,6,8a-hexahydro-naphthalene-2,6-dione(1),together with seven known compounds anti-HH-dimer-coumarin(2),(-)-5-exo-hydroxy-bomeol(3),O-hydroxyl cinnamic acid(4),9β-hydroxy-ageraphorone(5),10Hα-9-oxo-ageraphorone(6),10Hβ-9-oxo-ageraphorone(7)and 9-oxo-10,11-dehydroageraphorone 8,was isolated from the leaves of Eupatorium adenopho-rum Spreng.The structures were elucidated by IR,~1H and ~(13)C NMR,EIMS,HMBC and single-crystal X-ray spec-tral data.     

A Convenient Synthesis of 2,3‐Dihydro‐4H‐thiopyrano[2,3‐b]‐, ‐[2,3‐c]‐, or ‐[3,2‐c]pyridin‐4‐ones by the Reaction of the Corresponding 1‐(Chloropyridinyl)alk‐2‐en‐1‐ones with NaSH

2,3‐Dihydro‐4H‐thiopyrano[2,3‐b]pyridin‐4‐ones 4 were prepared by a three‐step sequence from commercially available 2‐chloropyridine ( 1 ). Thus, successive treatment of 1 with ⁱPr₂NLi (LDA) and α,β‐unsaturated aldehydes gave 1‐(2‐chloropyridin‐3‐yl)alk‐2‐en‐1‐ols 2 , which were oxidized with MnO₂ to 1‐(2‐chloropyridin‐3‐yl)alk‐2‐en‐1‐ones 3 . The reactions of 3 with NaSH?n H₂O proceeded smoothly at 0° in DMF to provide the desired thiopyranopyridinones. Similarly, 2,3‐dihydro‐4H‐thiopyrano[2,3‐c]pyridin‐4‐ones 8 and 2,3‐dihydro‐4H‐thiopyrano[3,2‐c]pyridin‐4‐ones 12 were obtained starting from 3‐chloropyridine ( 5 ) and 4‐chloropyridine ( 9 ), respectively.     

Two New Pentacyclic Triterpenes from Abelmoschus esculentus

Two new pentacyclic triterpenes, (3β,21β)‐19,21‐epoxylup‐20(29)‐en‐3‐yl acetate ( 1 ) and (3β)‐9,18‐dihydroxyolean‐12‐en‐3‐yl acetate ( 2 ), were isolated from Abelmoschus esculentus (L.) Moench . Their structures were determined on the basis of detailed analyses of their 1D‐ and 2D‐NMR‐spectroscopic and MS data.     

Vinmajorines C – E,Monoterpenoid Indole Alkaloids from Vinca major

Three new monoterpenoid indole alkaloids, vinmajorines C–E ( 1 – 3 ), along with 18 known analogues ( 4 – 21 ), were isolated from the whole plants of Vinca major. The new structures were elucidated as (5α,15β,16R,17α,19β,20α,21β)‐10,17‐dimethoxy‐21‐methyl‐18‐oxa‐5,16‐cycloyohimban‐19‐ol ( 1 ), (5α,15β,16R,17α,20α,21β)‐10‐methoxy‐21‐methyl‐18‐oxa‐5,16‐cycloyohimban‐17‐ol ( 2 ), and (5α,15β,16R,17α,20α,21β)‐10‐methoxy‐21‐methyl‐18‐oxa‐5,16‐cycloyohimban‐17‐yl acetate ( 3 ), respectively, by extensive NMR and MS analysis and comparison with known compounds. Compounds 1 – 3 were evaluated for their cytotoxic activities against five human cancer cell lines, compounds 1 and 3 showing moderate cytotoxic activities.     

Baimantuoluosides A – C,Three New Withanolide Glucosides from the Flower of Datura metel L.

In search for bioactive compounds from the flower of Datura metel L., three new withanolide glucosides, namely baimantuoluosides A, B, and C ( 1 – 3 , resp.) were isolated. Enzymatic hydrolysis of 1 – 3 afforded the corresponding aglycones 1a, 2a , and 3a , respectively. The structures of the new compounds were elucidated as (5α,6α,7α,12β,22R)‐5,12‐dihydroxy‐1,26‐dioxo‐6,7 : 22,26‐diepoxyergosta‐2,24‐dien‐27‐yl β‐D ‐glucopyranoside ( 1 ), (5α,6α,7α,12α,22R)‐5,12‐dihydroxy‐1,26‐dioxo‐6,7 : 22,26‐diepoxyergosta‐2,24‐dien‐27‐yl β‐D ‐glucopyranoside ( 2 ), (5α,6α,7α,22R)‐5‐hydroxy‐1,26‐dioxo‐6,7 : 22,26‐diepoxyergosta‐2,24‐dien‐27‐yl β‐D ‐glucopyranoside ( 3 ) on the basis of chemical and physicochemical evidence, and are further confirmed by the structure determination by X‐ray diffraction of withanolide aglycone 1a .