Total synthesis of junionone, a natural monoterpenoid from Juniperus communis L., and determination of the absolute configuration of the naturally occurring enantiomer by ROA spectroscopy

Recently, we reported a novel access to 2,2-diethyl-3-[(E/Z)-prop-1-en-1-yl]cyclobutanone by an intramolecular nucleophilic substitution with allylic rearrangement (S(N)i') of (E)-6-chloro-3,3-diethylhept-4-en-2-one. The ring closure reaction was found to proceed with selective syn-displacement of the leaving group. This method was now applied to the total synthesis of junionone, an olfactorily interesting cyclobutane monoterpenoid isolated from Juniperus communis, L. S(N)i' Ring closure of the ketone enolate of (E)-3,3-dimethyl-5-[(2R,3R)-3-methyloxiran-2-yl]pent-4-en-2-one (R,R)-(E)-4' proceeded only after the epoxide moiety had been activated by Lewis acid and led to the junionone precursors (3R)- and (3S)-3-[(1E,3R)-3-hydroxybut-1-en-1-yl]-2,2-dimethylcyclobutanone (S/R,R)-(E)-3. The ratio of syn- and anti-conformers in the transitory molecular arrangement was found to depend on the nature of the Lewis acid. The absolute configuration of both the synthetic as well as the natural junionone, isolated from juniper berry oil, was determined by Raman Optical Activity (ROA) spectroscopy. Our experiments led to a novel synthetic route to both (+)- and (-)-junionone, the first determination of the absolute configuration of natural junionone, and to the development of a practical ROA procedure for measuring milligram quantities of volatile liquids.     

Cytotoxic steroidal saponins from Polygonatum punctatum

Four new steroidal saponins, polypunctosides A-D (1-4, resp.), were isolated from the rhizomes of Polygonatum punctatum, together with five known steroidal saponins. On the basis of chemical and spectral evidence, the structures of the new saponins were established as (3beta,23S,25R)-23-(alpha-L-arabinopyranosyloxy)spirost-5-en-3-yl 4-O-(6-deoxy-alpha-L-mannopyranosyl)-D-glucopyranoside (1), (3beta,23S,25R)-23-[(2-O-acetyl-alpha-L-arabinopyranosyl)oxy]spirost-5-en-3-yl 4-O-(6-deoxy-alpha-L-mannopyranosyl)-D-glucopyranoside (2), (3beta,23S,25R)-23-[(3-O-acetyl-alpha-L-arabinopyranosyl)oxy]spirost-5-en-3-yl 4-O-(6-deoxy-alpha-L-mannopyranosyl)-D-glucopyranoside (3), and (3beta,23S,25R)-23-[(4-O-acetyl-alpha-L-arabinopyranosyl)oxy]spirost-5-en-3-yl 4-O-(6-deoxy-alpha-L-mannopyranosyl)-D-glucopyranoside (4). The cytotoxic activity of the isolated saponins was evaluated towards HeLa cells.     

In Silico Analog Design for Terbinafine Against Trichophyton rubrum: A Preliminary Study

The diseases caused by dermatophytes are common among several other infections which cause serious threat to human health. It is evident that enzyme squalene epoxidase is responsible for prolonged dermatophyte infection and it is appealing to note that this enzyme is also responsible for fatty acid synthesis in these groups of fungi. In the present study, terbinafine drug which targets enzyme squalene epoxidase has been explored to design its various novel analogues. The present study suggests that many more prominent drug analogues could be constituted which may be crucial towards designing new drug candidates. In the present study, we have designed a series of such analogues viz. [(2E)-6,6-dimethylhept-2-en-4-yn-1-yl](methyl)(naphthalen-1-ylmethyl)amine, N-[8-({[(2E)-6,6-dimethylhept-2-en-4-yn-1-yl](methyl)amino}methyl)naphthalen-1-yl]-2-(sulfoamino) acetamide, {[4-(dihydroxyamino)-8-({[(2E)-6,6-dimethylhept-2-en-4-yn-1-yl](methyl)amino}methyl)naphthalen-1-yl]sulfanyl}methanol and (R)-{[4-({[(2E,6R)-6,7-dimethyloct-2-en-4-yn-1-yl](methyl)amino}methyl)-5-[(hydroxysulfamoyl)amino]naphthalen-1-yl]amino}sulfinic acid. Moreover, further by molecular docking approach the binding between enzyme and designed analogues was further analysed. The present preliminary report suggested a considerably good docking interaction score of −338.75 kcal/mol between terbinafine and squalene epoxidase from Trichophyton rubrum. This preliminary study implies that few designed candidate ligands can be effectual towards the activity of this enzyme and can play crucial role in pathogenesis control of T. rubrum.     

Inhibition by prostacyclin and carbacyclins of endothelin-induced DNA synthesis in cultured vascular smooth muscle cells

Effects of prostacyclin and carbacyclins on endothelin-induced DNA synthesis were investigated in vascular smooth muscle cells. DNA synthesis was estimated by [3H]thymidine incorporation. Five carbacyclins used in this report were 5-[(1S, 5S, 6R, 7R)-7-hydroxy-6-[(E)-(S)-3-hydroxy-1-octenyl]bicyclo [3.3.0]oct-2-en-3-yl) pentanoic acid (TEI-7165), methyl 5-[(1S, 5S, 6R, 7R)-7-hydroxy-6-[(E)-(S)-3-hydroxy-1-octenyl]bicyclo[3.3.0]oct-2-en-3- yl]pentanoate (TEI-9090), 5-[(1S, 5S, 6R, 7R)-7-hydroxy-6-[(E)-(3S, 5S)-3-hydroxy-5-methyl-1-nonenyl]bicyclo[3.3.0]oct-2-en-3-yl)penta noic acid (TEI-9063), methyl 5-[(1S, 5S, 6R, 7R)-7-hydroxy-6-[(E)-(3S, 5S)-3-hydroxy-5-methyl-1- nonenyl]bicyclo[3.3.0]oct-2-en-3-yl)pentanoate (TEI-1324), 5-[(1S, 5S, 6R, 7R)-7-hydroxy-6-[(E)-(S)-4-hydroxy-4-methyl-1- octenyl]bicyclo[3.3.0]oct-2-en-3-yl] pentanoic acid (TEI-3356). Prostacyclin and the carbacyclins inhibited the endothelin-induced DNA synthesis within the nanomolar range. These results suggest that prostacyclin and carbacyclins are possibly effective in inhibiting the proliferation of vascular smooth muscle cells under some situations in vivo.     

9-deaza-5'-noraristeromycin

9-deaza-5'-noraristeromycin (2) has been prepared in 10 steps from the readily available (+)-(1R,4S)-4-t-butyldimethylsilyloxycyclopent-2-en-1-yl acetate. Compound 2 was evaluated against a large number of viruses. No activity was found nor did 2 display cyctotoxicity towards the viral host cells.     

New steroidal saponins from rhizomes of Costus spiralis

Two new steroidal saponins were isolated from the rhizomes of Costus spiralis Rosc. Their structures were established as (3beta,25R)-26-(beta-D-glucopyranosyloxy)-22-hydroxyfurost-5-en-3-yl O-D-apio-beta-D-furanosyl-(1-->2)-O-[alpha-L-rhamnopyranosyl-(1-->4)]-beta-D-glucopyranoside (1) and (3beta,25R)-26-(beta-D-glucopyranosyloxy)-22-hydroxyfurost-5-en-3-yl O-D-apio-beta-D-furanosyl-(1-->4)-O-[alpha-L-rhamnopyranosyl-(1-->2)]-beta-D-glucopyranoside (2). Their structural identifications were performed using detailed analyses of 1H and 13C NMR spectra including 2D NMR spectroscopic techniques (DEPT, COSY, HETCOR and COLOC) and chemical conversions. The steroidal saponins were evaluated for anti-inflammatory activity.     

Molecular docking based screening of neem-derived compounds with the NS1 protein of Influenza virus

AbbreviationsNS1 protein - Non Structural 1 proteinNA - Neuraminidase, HA - Hemagglutinin, M - Matrix, 127-40-2 - 4-[(1E, 3E, 5E,7Z, 9E, 11E, 13E, 15E, 17E)-18-(4-hydroxy-2,6,6-trimethylcyclohex-2-en-1-yl)-3,7,12,16-tetramethyloctadeca-1,3,5,7,9,11,13,15,17- nonaenyl]-3, 5, 5-trimethylcyclohex-3-en-1-ol, Quercitrin 2 - (3,4-dihydroxyphenyl)-5,7-dihydroxy-3- [(2S,3R,4R,5R,6S)-3,4,5-trihydroxy-6-methyloxan-2-yl]oxychromen-4-one, Tiplasinin 2 - [1-benzyl-5-[4-(trifluoromethoxy) phenyl] indol-3-yl]-2-oxoacetic acid, Hyperoside 2 - (3,4-dihydroxyphenyl)-5,7-dihydroxy-3- [(2S,3R,4S,5R,6R)-3, 4, 5-trihydroxy-6- (hydroxymethyl)oxan-2- yl]oxychromen-4-one LGH 4-(2-chloro-4-nitrophenyl)piperazin-1-yl][3-(2-methoxyphenyl)-5-methyl-1,2-oxazol-4-yl]methanone, nRUTIN 2 - (3, 4-dihydroxyphenyl) -5, 7-dihydroxy-3-[(2S, 3R, 4S, 5S, 6R)-3, 4, 5-trihydroxy-6-[[(2R, 3R, 4R, 5R, 6S)-3,4,5-trihydroxy- 6-methyloxan-2-yl]oxymethyl]oxan-2-yl]oxychromen-4-one.     

广东紫珠中的萜类化合物及其抗炎活性

对岭南药材广东紫珠(Callicarpa kwangtungensis)地上部分进行化学成分研究,得到11个萜类化合物,分别鉴定为sambucunlin A(1)、2α-羟基羽扇豆醇(2)、swinhoeic acid(3)、3β-羟基-乌苏烷-11-烯-13β,28-内酯(4)、蔷薇酸(5)、2α,3β,6β,18β,23-pentahydroxy-olean-12-en-28-oic acid(6)、rel-5-(3S,8S-dihydroxy-1R,5S-dimethyl-7-oxa-6-oxobicyclo-oct-8-yl)-3-methyl-2Z,4E-pentadienoic acid(7)、salvionoside B(8)、齐墩果酸(9)、白桦脂酸(10)和α-香树脂醇(11)。其中,化合物1～4和6～8为首次从该属植物中分离得到。在化学成分分离基础上,进一步选择脂多糖(LPS)诱导的RAW 264.7小鼠巨噬细胞炎症模型进行萜类化合物抗炎活性测试。结果表明:化合物3和9具有显著的抗炎活性,对比结构发现,三萜类化合物(3～6、9和11)抗炎活性优于倍半萜类化合物(7和...     

3-Deoxy-3,4-dehydro analogs of XM462. Preparation and activity on sphingolipid metabolism and cell fate

Three analogs of the dihydroceramide desaturase inhibitor XM462 are reported. The compounds inhibit both dihydroceramide desaturase and acid ceramidase, but with different potencies depending on the N-acyl moiety. Other enzymes of sphingolipid metabolism, such as neutral ceramidase, acid sphingomyelinase, acid glucosylceramide hydrolase, sphingomyelin synthase and glucosylceramide synthase, are not affected. The effect on the sphingolipidome of the two best inhibitors, namely (R,E)-N-(1-hydroxy-4-(tridecylthio)but-3-en-2-yl)octanamide (RBM2-1B) and (R,E)-N-(1-hydroxy-4-(tridecylthio)but-3-en-2-yl)pivalamide (RBM2-1D), is in accordance with the results obtained in the enzyme assays. These two compounds reduce cell viability in A549 and HCT116 cell lines with similar potencies and both induced apoptotic cell death to similar levels than C8-Cer in HCT116 cells. The possible therapeutic implications of the activities of these compounds are discussed.     

Further constituents of Galianthe thalictroides (Rubiaceae) and inhibition of DNA topoisomerases I and IIα by its cytotoxic β-carboline alkaloids

A new cytotoxic β-carboline alkaloid, 1-methyl-3-(2-hydroxypropan-2-yl)-2-(5-methoxy-9H-β-carbolin-1-yl)-cyclopentanol (1), was isolated from roots of Galianthe thalictroides, together with the alkaloid 1-(hydroxymethyl)-3-(2-hydroxypropan-2-yl)-2-(5-methoxy-9H-β-carbolin-1-yl)-cyclopentanol (2), the anthraquinones 1-methyl-alizarin and morindaparvin-A, the coumarin scopoletin, homovanillic alcohol, (−)-epicatechin, and the steroids stigmast-4-en-3-one, 4,22-stigmastadien-3-one, campest-4-en-3-one, stigmast-4-en-3,6-dione, 6-β-hydroxy-stigmast-4-en-3-one, stigmasterol, campesterol, β-sitosterol, and β-sitosterol-3-O-β-d-glucopyranoside. Among the previously known compounds, homovanillic alcohol is a novel finding in Rubiaceae, while 1-methyl-alizarin, morindaparvin-A, scopoletin, stigmast-4-en-3-one, 4,22-stigmastadien-3-one, campest-4-en-3-one, stigmast-4-en-3,6-dione, and 6-β-hydroxy-stigmast-4-en-3-one is reported for the first time in the genus Galianthe. The cytotoxic β-carboline alkaloids 1 and 2 exhibited potent antitopoisomerase I and IIα activities and strong evidence is provided for their action as topoisomerase IIα poisons and redox-independent inhibitors.     

Synthesis, in vitro pharmacology, and pharmacokinetic profiles of 2-[1-amino-1-carboxy-2-(9H-xanthen-9-yl)-ethyl]-1-fluorocyclopropanecarboxylic acid and its 6-heptyl ester, a potent mGluR2 antagonist

In this paper, we describe the synthesis of (+)-(1R( *),2R( *))-2-[(1S( *))-1-amino-1-carboxy-2-(9H-xanthen-9-yl)-ethyl]-1-fluorocyclopropanecarboxylic acid (+)-16a, a compound, that is, fluorinated at the alpha position of the carboxylic acid in the cyclopropane ring of a group II mGluRs antagonist, 1 (LY341495), using a previously reported stereoselective cyclopropanation reaction. The fluorinated compound (+)-16a exhibited almost the same affinity (IC(50)=3.49 nM) for mGluR2 as 1 but had a superior pharmacokinetic profile. Furthermore, a marked elevation of the plasma levels of (+)-16a was observed following the administration of a prodrug, (+)-17.     

Polyhydroxylated steroidal constituents from the fresh rhizomes of Tupistra yunnanensis

Six new polyhydroxylated steroidal saponins, tupistrosides A-F (1-6), together with nine known steroids, were isolated from the fresh rhizomes of Tupistra yunnanensis. Their structures were elucidated to be (25S)-1beta,4beta,5beta-trihydroxy-spirostane-3beta-yl O-alpha-l-arabinopyranoside (1), 1beta,24beta-dihydroxy-spirost-5,25(27)-dien-3alpha-yl O-beta-d-glucopyranoside (2), (22S,25S)-1alpha,2beta,3alpha,5alpha-tetrahydroxy-furo-spirostane-26-yl O-beta-d-glucopyranoside (3), 1beta,3alpha,22 xi-trihydroxy-furost-5,25(27)-dien-26-yl O-beta-d-glucopyranoside (4), 26-O-beta-d-glucopyranosyl-1beta,22-dihydroxy-furost-5-en-3alpha-yl O-beta-d-glucopyranoside (5) and 22-methoxy-1beta,2beta,3beta,4beta,5beta,7alpha-hexahydroxy-furost-25(27)-en-6-one-26-yl O-beta-d-glucopyranoside (6), respectively, by means of spectroscopic analysis and the results of acid hydrolysis.     

Evolution of novel tricyclic CRTh2 receptor antagonists from a (E)-2-cyano-3-(1H-indol-3-yl)acrylamide scaffold

(E)-2-(3-(3-((3-Bromophenyl)amino)-2-cyano-3-oxoprop-1-en-1-yl)-1H-indol-1-yl)acetic acid (1) was discovered in a HTS campaign for CRTh2 receptor antagonists. An SAR around this hit could be established and representatives with interesting activity profiles were obtained. Ring closing tactics to convert this hit series into a novel 2,3,4,5-tetrahydro-1H-pyrido[4,3-b]indole based CRTh2 receptor antagonist series is presented.     

Probes for narcotic receptor mediated phenomena. Part 28: new opioid antagonists from enantiomeric analogues of 5-(3-hydroxyphenyl)-N-phenylethylmorphan

Enantiomeric analogues of 5-(3-hydroxyphenyl)morphan ligands were synthesized and evaluated because of our unexpected finding that opioid antagonists can be obtained in the 5-phenylmorphan series of opioids without sterically hindering the rotation of the phenolic ring. We determined the opioid receptor binding affinity of these new analogues, as well as the efficacy of the more interesting ligands. One of the new compounds [(1R,5S)-(-)-3-[2-(3'-phenylpropyl)-2-azabicyclo[3.3.1]non-5-yl]-phenol, 15] was found to have half of the efficacy of naloxone, a potent opioid antagonist, in the [(35)S]GTPgammaS assay, and two others (1R,5S)-(-)-3-[2-(4'-phenylbutyl)-2-azabicyclo[3.3.1]non-5-yl]-phenol, 17, and (1R,5S,1'S)-(+)-3-[2-(1'-methyl-2'-phenylethyl)-2-azabicyclo[3.3.1]non-5-yl]-phenol, 26, acted as moderately potent opioid antagonists. X-ray crystallographic structure data were obtained on three compounds. Two of them had three chiral centers; 25 [(1R,5S,1'R)-(-)-3-[2-(1'-methyl-2'-phenylethyl)-2-azabicyclo[3.3.1]non-5-yl]-phenol] was determined to have the 1R,5S,1'R configuration, and 26 the 1R,5S,1'S configuration. Since (1S,5R)-(+)-2-bromo-5-[2-(2'-phenylethyl)-2-azabicyclo[3.3.1]non-5-yl]-phenol (32) was a position isomer of (1S,5R)-(+)-4-bromo-3-[2-(2'-phenylethyl)-2-azabicyclo[3.3.1]non-5-yl]-phenol (30), and both showed the same 1H NMR spectrum, the structure of 32 was unequivocally determined by X-ray structure analysis.     

Modulation of sodium pumps by steroidal saponins

Costus spicatus, used in Brazilian traditional medicine to expel kidney stones, contains steroidal saponins with different chemical characteristics. In spite of its popular utilization as potent diuretic, no scientific reports correlate this activity with the chemical constituents of the extract. Therefore, two steroidal saponins (3 beta,22 alpha,25R)-26-(beta-D-glucopyranosyloxy)-2-methoxyfurost-5-en-3-yl O-D-apio-beta-D-furanosyl-(1-->2)-O-[6-deoxy-alpha-L-mannopyranosyl-(1-->4)]-beta-D-glucopyranoside (1) and (3 beta,22 alpha,25R)-spirostan-3-yl O-D-apio-beta-D-furanosyl-(1-->2)-O-[6-deoxy-alpha-L-mannopyranosyl-(1-->4)]-beta-D-glucopyranoside (1a), were isolated from the rhizomes of this plant and their effects on the Na+-ATPase and (Na+ + K+)-ATPase activities of the proximal tubule from pig kidney were evaluated. It was observed that 1 and 1a inhibit specifically the Na+-ATPase activity.     

Sar studies of piperidine-based analogues of cocaine. Part 3: oxadiazoles

The synthesis of novel 4beta-aryl-1-methyl-3alpha-(3-substituted-1,2,4-oxadiazol-5-yl)piperidines, bioisosteres of ester (+)-1, is described. The synthesized oxadiazoles were evaluated for their affinity to the DAT and their ability to inhibit monoamine reuptake at the DAT, NET, and 5HTT. The results show that affinity to the DAT and ability to inhibit the reuptake at the DAT, NET, and 5HTT is a function of the size of the substituent in the oxadiazole ring. (+)-(3R,4S)-4beta-(4-Chlorophenyl)-1-methyl-3alpha-(3-methyl-1,2,4-oxadiazol-5-yl)piperidine [(+)-2a], which is structurally and pharmacologically most similar to the ester (+)-1 in this series, showed at least a 2-fold longer duration of action when compared to ester (+)-1.     

Steroidal glycosides from the rhizomes of Ruscus hypophyllum

Seven steroidal glycosides, along with one known glycoside, were isolated from the rhizomes of Ruscus hypophyllum (Liliaceae). Comprehensive spectroscopic analysis, including 2D NMR spectroscopy, and the results of acid hydrolysis allowed the chemical structures of the compounds to be assigned as (23S,25R)-23-hydroxyspirost-5-en-3beta-yl O-alpha-l-rhamnopyranosyl-(1-->4)-beta-d-glucopyranoside (1), 1beta-hydroxyspirosta-5,25(27)-dien-3beta-yl O-alpha-l-rhamnopyranosyl-(1-->4)-beta-d-glucopyranoside (2), (22S)-16beta,22-dihydroxycholest-5-en-3beta-yl O-alpha-l-rhamnopyranosyl-(1-->4)-beta-d-glucopyranoside (3), (22S)-16beta-[(beta-d-glucopyranosyl)oxy]-22-hydroxycholest-5-en-3beta-yl O-alpha-l-rhamnopyranosyl-(1-->4)-beta-d-glucopyranoside (4), (22S)-16beta-[(beta-d-glucopyranosyl)oxy]-22-hydroxycholest-5-en-3beta-yl beta-d-glucopyranoside (5), (22S)-16beta-[(beta-d-glucopyranosyl)oxy]-3beta,22-dihydroxycholest-5-en-1beta-yl O-alpha-l-rhamnopyranosyl-(1-->2)-(3,4-di-O-acetyl-beta-d-xylopyranoside) (6), and (22S)-16beta-[(beta-d-glucopyranosyl)oxy]-3beta,22-dihydroxycholest-5-en-1beta-yl O-alpha-l-rhamnopyranosyl-(1-->2)-O-[beta-d-xylopyranosyl-(1-->3)]-beta-d-xylopyranoside (7), respectively. This is the first isolation of a series of cholestane glycosides from a Ruscus species.     

A furostanol glycoside from rhizomes of Costus spicatus.

A new furostanol glycoside was isolated from the rhizomes of Costus spicatus. Its structure was established as (3 beta,22 alpha,25R)-26-(beta -D-glucopyranosyloxy)-22-methoxyfurost-5-en-3-yl O-D-apio-beta-D-furanosyl-(1-->2)-O-[6-deoxy-alpha-L-mannopyranosy l-(1-->4)]- beta-D-glucopyranoside. The structural identification was performed using detailed analysis of 1H and 13C NMR spectra including 2D NMR spectroscopic techniques (COSY, HETCOR and COLOC) and chemical conversions.     

Further farnesyl-homogentisic acid derivatives from Otoba parvifolia

The seeds of Otoba parvifolia contain three novel compounds apparently derived from homogentisic acid, rel-(1′R,5′R)-2-(1′-farnesyl-5′-hydroxy-2′-oxocyclohex-3′-en-1′-yl)-acetic acid and its acetate as well as rel-(1′R,4′S,5′R)-2-(1′-farnesyl-4′,5′-dihydroxy-2′-oxocyclohexan-1′-yl)-acetic acid δ-lactone. The structure of an additional isolate, previously described as 2-(1′-farnesyl-2′-hydroxy-5′-oxocyclohex-3′-en-1′-yl)-acetic acid γ-lactone was revised to rel-(1′R,5′R)-2-(1′-farnesyl-5′-hydroxy-2′-oxocyclohex-3′-en-1′-yl)-acetic acid δ-lactone.     

Phytosterols from Murraya exotica

From the cyclohexane extract of the leaves of Murraya exotica, five novel phytosterols: (23S)-23-ethyl-24-methyl-cycloart-24(24¹)-en-3β-ol; 3β-methoxy-(23S)-23-ethyl-24-methyl-cycloart-24(24¹)-en-3β-ol; (23 S)-23-ethyl-24-methyl-cycloart-24(24¹)-3β-yl acetate; (23ξ)-23-isopropyl-24-methyl-cycloart-25-en-3β-ol and (23ξ)-23-isopropyl-24-methyl-cycloart-25-en-3β-yl acetate have been isolated. Structural elucidation of the isolated compounds is based on physical, chemical and spectral analysis including IR, ¹H and ¹³CNMR and mass spectrometry.