Studies on the metabolism of gomisin A (TJN-101). II. Structure determination of biliary and urinary metabolites in rat

After oral administration of gomisin A (1) to rats, the bile and urine were collected and treated with beta-glucuronidase and arylsulfatase. Seven metabolites, met B (2), met A-III (3), met E (4), met D (5), met F (6), met G (7), and met H (8) were isolated from the bile treated with the enzymes. Eight metabolites 2-8, and met A-II (9) were isolated from the urine treated with the enzymes. A major metabolite 2, and two minor metabolites 3 and 9 were identified as met B, met A-III, and met A-II, respectively, which are oxidative products of 1 formed by rat liver S9 mix. The structures of five new metabolites 4-7, and 8 were determined on the basis of chemical and spectral studies.     

Rumphellolides A-F, six new caryophyllane-related derivatives from the Formosan Gorgonian coral Rumphella antipathies

Six new caryophyllane-related natural products, including two carboxylated sesquiterpenoids, rumphellolides A (1) and B (2), and four norsesquiterpene alcohols, rumphellolides C-F (3-6), were isolated from the Formosan gorgonian coral Rumphella antipathies. The structures of the above new natural products were established on the basis of extensive spectral data analysis. Rumphellolides A (1), D (4), E (5), and F (6) showed weak antibacterial activity.     

Terpenoid-related metabolites from a formosan soft coral Nephthea chabrolii

Two new sesquiterpenoidal natural products chabrolidiones A and B (1 and 2), two C(18) terpenoid-related carboxylic acids, ketochabrolic acid (3) and isoketochabrolic acid (4), and one naphthoquinone derivative chabrolonaphthoquinone C (5), along with two known compounds (+)-aristolone (6) and teuhetenone A (7) were isolated from a Formosan soft coral Nephthea chabrolii. The structures of the new metabolites were determined on the basis of extensive spectroscopic analysis and by comparison of NMR data with those of related metabolites. Metabolite 1 has been synthesized previously, but was isolated for the first time from natural sources. Cytotoxic activity of metabolites 1-3 and 5-7 against a limited panel of cancer cell lines is also described.     

Biocatalyzed cross-coupling of sinomenine and guaiacol by Antrodiella semisupina

In search of more potent derivatives of sinomenine (1), a clinically available natural alkaloid for the treatment of rheumatoid arthritis (RA), biocatalyzed cross-coupling of sinomenine and guaiacol (2) by Antrodiella semisupina, provided two unique C-C coupled (3 and 4) and one C-O linked (5) novel metabolites. The structures of the metabolites were elucidated by means of MS, 2D NMR techniques and X-ray analysis. 4 exhibited more potent inhibitory activity on IL-6 production than 1 in human synovial sarcoma cell (SW982), and 5 stimulated IL-6 production.     

Chemical constituents of Cichorium intybus and their inhibitory effects against urease and alpha-chymotrypsin enzymes

Phytochemical investigation of the aerial parts of Cichorium intybus L. resulted in the isolation and identification of two new natural metabolites, 2,6-di[but-3(E)-en-2-onyl]naphthalene (1), and 3,3',4,4'-tetrahydroxychalcone (2), along with nine known compounds. Their structures were determined by spectroscopic techniques including 1D and 2D NMR. The known compounds were identified as scopoletin (3), 4-hydroxyphenylacetic acid (4), 3-hydroxy-4-methoxybenzoic acid (5), 4,4'-dihydroxychalcone (6), 6,7-dihydroxycoumarine (7), 1-triacontanol (8), lupeol (9), beta-sitosterol (10), and beta-sitosterol-3-O-beta-glucopyranoside (11). Compounds 4-6 and 8 are reported for the first time from C. intybus. Compounds 2 and 3 showed weak inhibitory activities against urease and alpha-chymotrypsin enzymes, respectively.     

Tyromycic acids F and G: two new triterpenoids from the mushroom Tyromyces fissilis

Phytochemical examination of the methanol extract of the fruit bodies of the Japanese fungus Tyromyces fissilis led to the isolation of two new lanostane derivatives called tyromycic acids F (1) and G (2), together with two known compounds, tyromycic acid (3) and trametenolic acid B (4). Their structures were identified by 2D NMR, IR, and UV spectroscopy.     

Tyrosinase inhibitory potential of natural products isolated from various medicinal plants

Seven secondary metabolites, p-hydroxybenzoic acid (1), 3,4-dihydroxybenzoic acid (2), ferulic acid (3), 2,6-dimethoxy-4-hydroxy acetophenone (4), lupeol (5), 2'-O-ethylmurrangatin (6) and hibiscetin heptamethyl ether (7) were the natural products isolated from various medicinal plants. Their structures were identified by spectral comparison with previously reported data. The compounds 1-7 were screened for their tyrosinase-inhibitory activity. The compound p-hydroxybenzoic acid (1) was found to have potent activity against tyrosinase enzyme, whereas lupeol (5) showed significant activity.     

Structure elucidation and NMR assignments for two amide alkaloids from a Mangrove endophytic Fungus (No. ZZF-22)

The structure elucidations and complete (1)H and (13)C NMR assignments are reported for two new natural products: 3-benzylidene-8,8a-dihydroxy-2-methyl-hexahydro-pyrrolo[1,2-a]pyrazine-1,4-dione(1) and 4-hydroxy-6-(hydroxy-phenyl-methyl)-N-(3-methyl-butyryl)-nicotinamide (2). Both of these secondary metabolites were isolated from the fermentation medium of a Mangrove endophytic fungus. High resolution electron impact mass spectrometry (HREIMS), FT-IR Spectroscopy and NMR experiments including gCOSY, gHMQC, gHMBC and NOE were used for determination of the structures and assignments of the amide alkaloids.     

New oleanene glycosides from the leaves of Acanthopanax japonicus

The structures of 6 new oleanene glycosides (1--6) isolated from the leaves of Acanthopanax japonicus FRANCH et. SAVART (Araliaceae) were elucidated by mass, 1D, and 2D NMR spectroscopy. The structures of 1--6 were established as 28-O-[alpha-L-rhamnopyranosyl-(1-->4)-beta-D-glucopyranosyl-(1-->6)-beta-D-glucopyranosyl] ester of 3beta,23-dihydroxy-olean-12-en-28,29-dioic acid, 3beta,30-dihydroxy-olean-12-en-23,28-dioic acid, 3beta,29-dihydroxy-olean-12-en-23,28-dioic acid (=dianic aicd), 3beta-dihydroxy-olean-12-en-23,28-dioic acid (=gypsogenic acid), 3beta,29-dihydroxy-23-oxo-olean-12-en-28-oic acid, and 3beta-hydroxy-23-oxo-olean-12-en-28,29-dioic acid, designated acanjaposide D (1), E (2), F (3), G (4), H (5), and I (6), respectively.     

Iridoids from Neopicrorhiza scrophulariiflora and their hepatoprotective activities in vitro

Four new non-glycosidic iridoids, piscrocins D (1), E (2), F (6), and G (7), as well as two new iridoid glycosides, piscrosides A (8) and B (9), were isolated from the roots of Neopicrorhiza scrophulariiflora (Scrophulariaceae), together with seven known iridoids. The structures of the isolated compounds were established by means of 1D and 2D NMR spectroscopy and chemical methods. The hepatoprotective activities of these compounds were evaluated by measuring their effects on CCl(4)-induced hepatocytes damage in vitro, and the structure-activity relationships were also discussed.     

Novel 2‐Arylbenzofuran Derivatives from Artocarpus petelotii

Further phytochemical investigations on the root barks of Artocarpus petelotii Gagnep afforded four novel isoprenylated 2‐arylbenzofuran derivatives, namely artopetelins D–G ( 1 – 4 ). Their structures were elucidated by spectroscopic methods, mainly by 2D‐NMR techniques. The biogenetic origins of artopetelins F and G ( 3 and 4 ) were also postulated.     

Antimicrobial Polyketide Metabolites from Penicillium bissettii and P. glabrum

Screening of several fungi from the New Zealand International Collection of Microorganisms from Plants identified two strains of Penicillium, P. bissettii and P. glabrum, which exhibited antimicrobial activity against Escherichia coli, Klebsiella pneumoniae, and Staphylococcus aureus. Further investigation into the natural products of the fungi, through extraction and fractionation, led to the isolation of five known polyketide metabolites, penicillic acid (1), citromycetin (2), penialdin A (3), penialdin F (4), and myxotrichin B (5). Semi-synthetic derivatization of 1 led to the discovery of a novel dihydro (1a) derivative that provided evidence for the existence of the much-speculated open-chained form of 1. Upon investigation of the antimicrobial activities of the natural products and derivatives, both penicillic acid (1) and penialdin F (4) were found to inhibit the growth of Methicillin-resistant S. aureus. Penialdin F (4) was also found to have some inhibitory activity against Mycobacterium abscessus and M. marinum along with citromycetin (2).     

Variations of structures and gas sorption properties of three coordination polymers induced by fluorine atom positions in azamacrocyclic ligands

Three coordination polymers of [(NiL(1))(3)(TCBA)(2)] (1), [(NiL(2))(3)(TCBA)(2)] (2), and [(NiL(3))(3)(TCBA)(2)] (3) have been constructed using azamacrocyclic Ni(II) complexes [NiL(1)](ClO(4))(2)/[NiL(2)](ClO(4))(2)/[NiL(3)](ClO(4))(2) and TCBA(3-) as building blocks (L(1) = 3,10-bis(2-fluorobenzyl)-1,3,5,8,10,12-hexaazacyclotetradecane; L(2) = 3,10-bis(3-fluorobenzyl)-1,3,5,8,10,12-hexaazacyclotetradecane; L(3) = 3,10-bis(4-fluorobenzyl)-1,3,5,8,10,12- hexaazacyclotetradecane; TCBA(3-) = tri(4-carboxy-benzyl)amine). The results of X-ray diffraction analyses reveal that 1 shows a 2D Borromean structure, while 2 and 3 form 2D layer structures, and the 2D layers are further connected by the interlayer F···F interactions in 2 and C-H···F interactions in 3 to generate two 3D porous structures with 1D fluorine atoms interspersed channels. Gas sorption measurements illustrate that the desolvated 2 and 3can adsorb N(2), H(2), and CO(2) molecules. The different structures and gas sorption properties of 1 and 2/3 are mainly induced by the different positions of F atoms in azamacrocycle ligands.     

Two New 3,4‐seco‐Cycloartane Triterpenes from Gardenia sootepensis

Two new 3,4‐seco‐cycloartane triterpenes, named sootepin F ( 1 ) and sootepin G ( 2 ), together with two known compounds, coronalolide methyl ester ( 3 ) and sootepin D ( 4 ), were isolated from the leaves and twigs of Gardenia sootepensis. Their structures were elucidated on the basis of 1D‐ and 2D‐NMR experiments, including HMBC, HSQC, ¹H,¹H‐COSY, and ROESY, as well as HR‐MS.     

Three abietane diterpenes and two diterpenes incorporated sesquiterpenes from the bark of Cryptomeria japonica

Three new abietane diterpenes, sugikurojins D (1), E (2), and F (3), and two new abietanes which incorporate cadinane, sugikurojins G (4) and H (5) were isolated from the bark of Cryptomeria japonica. These structures were elucidated primarily by extensive NMR experiments. The structure of sugikurojin D (1) was deduced to be 6alpha-acetoxy-7beta,11-dihydroxy-12-methoxy-8,11,13-abietatriene. Sugikurojin E (2) was deduced to be 6alpha-acetoxy-7beta,12-dihydroxy-8,11,13-abietatriene. Sugikurojin F (3) was 7alpha-methoxy-8,13-abietadien-11,12-dione. Sugikurojins G (4) and H (5) had a unique skeleton incorporating an alpha-cadinol or a 1alpha-hydroxy-T-cadinol in ferruginol, respectively. Also obtained in this investigation were the known diterpenes (6-14). An antibacterial activity of ten among these against Staphylococcus aureus and Escherichia coli was inactive at the (MIC: 125 microg/ml) level. Meanwhile, in the cytotoxic activity against HL-60, compounds 4, 8, and 11 showed moderate (IC50: 4, 35.4; 8, 28.0; 11, 52.4 microM) though weak (IC50: 4, 100; 8, 80.8; 11, 100 microM) activity against HCT-15.     

The pregnane derivatives of the seeds from Dregea abyssinica (Hochst.) K. Schum. (Asclepiadacea). II. Structure determination

The total or partial structure determinations of some new components from Dregea abyssinica are reported. The four drebyssogenins (F, G, J and H) are esters of the drevogenins P ( 7 ) and D( 9 ) and have the following structures: Drebyssogenin F ( 5 ) = 11-O-acetyl-12-O-(α-hydroxyisovaleryl)-drevogenin P, drebyssogenin G ( 14 ) = 11-O-acetyl-12-O-isovaleryl-drevogenin D, drebyssogenin J ( 15 ) = 11, 12-di-O-acetyl-drevogenin D. Drebyssogenin K is a mixture of K1 ( 16 ) and K2 ( 17 ), the mono-O-tiglyl and mono-O-isovaleryl derivatives of drevogenin D respectively, with as yet undetermined position of the acyl residues. The drebyssosides 1, 2 and 3 are glycosides of trisaccharides. Drebyssoside 1 ( 2 ) is pachybiosyl-cymarosyl-drevogenin A, drebyssoside 2 ( 3 ) asclepobiosyl-cymarosyl-drevogenin A and drebyssoside 3 ( 6 ) pachybiosyl-cymarosyl-drebyssogenin F. Drebyssoside 4 is a mixture of at least two components and contains the same aglycones and the same sugar units as the drebyssosides 1 and 3, but is different from them. The full structure of the two sugars (drebyssobiose ( 25 ) and sugar T ( 24 )) has not been determined; it is only shown that both are disaccharides which contain 3-O-methyl-6-deoxy-allose linked to a 2-deoxyhexose.     

Rearranged vibsane-type diterpenes from Viburnum awabuki and photochemical reaction of vibsanin B

Nine new diterpenes, neovibsanin D (1), 7-epi-neovibsanin D (2), 15-O-methylneovibsanin F (3), 14-epi-15-O-methylneovibsanin F (4), 15-O-methyl-18-oxoneovibsanin F (5), 2-O-methylneovibsanin H (6), 2-O-methylneovibsanin I (7), neovibsanin G (8), and 14-epi-neovibsanin G (9), were isolated from a methanol extract of the leaves of Viburnum awabuki. Their structures were elucidated to be uniquely rearranged vibsane-type diterpenes by spectroscopic analyses and comparison of NMR data with those of previously reported vibsane-type diterpenes. In addition, irradiation of vibsanin B (12) in methanol with a high-pressure Hg lump led to the direct formation of neovibsanins A (14) and B (15). These results gave a clue to understanding of the biogenetic interconversion of 11-membered vibsanins into neovibsanins.     

氟代苯阳离子的理论研究

用B3LYP方法及6-311G(d,p)和6-311 G(d,p)基组,对十二种氟代苯阳离子做了理论研究,优化了它们的电子基态的结构,计算了对应分子的垂直电离势(VIP)和绝热电离势(AIP)．依据Jahn．Teller理论,计算确定了1,3,5-C6H3F^ 3和C6F^ 6离子分别具有C2v(2↑B)和D2h(2↑B2g)结构(对应分子分别为D3h和D6h结构)．其余十个离子的构型的对称点群与对应分子相同,但构型参数值有明显差别．自然布居分析计算表明这些离子的正电荷主要分布在与F原子相连的C原子和各H原子上．B3LYP／6-311 G(d,p)级别上计算的各氟代苯分子的VIP和AIP值和实验值符合得很好．     

Olefin metathesis as an inorganic synthetic tool: cross and ring closing metathesis reactions of diruthenium-bound omega-alkene-alpha-carboxylates

Diruthenium compounds containing one omega-alkene-alpha-carboxylate ligand, Ru2Cl(D(3,5-Cl2Ph)F)3(O2C(CH2)nCH=CH2) (n=1 (1a) and 2 (1b)), were prepared from the reaction between Ru2Cl(D(3,5-Cl2Ph)F)3(O2CCH3) (D(3,5-Cl2Ph)F=N,N'-bis(3,5-dicholorophenyl)formamidinate) and the corresponding omega-alkene-alpha-carboxylic acid. Compounds 1a and 1b both underwent olefin cross metathesis reactions catalyzed by (Cy3P)2Cl2Ru(=CHPh) to afford the dimerized compounds [Ru2Cl(D(3,5-Cl2Ph)F)3]2(mu-O2C(CH2)nCH=CH(CH2)nCO2) (n=1 (2a) and 2 (2b)). Similarly, diruthenium compounds containing two omega-alkene-alpha-carboxylate ligands, cis-Ru2Cl(D(3,5-Cl2Ph)F)2(O2C(CH2)nCH=CH2)2 (n=1 (3a), 2 (3b), and 3 (3c)), were prepared by substituting the acetate ligands in cis-Ru2Cl(D(3,5-Cl2Ph)F)2(O2CCH3)2 with the corresponding omega-alkene-alpha-carboxylate ligands. Compounds 3 exhibited different reactivity under olefin metathesis conditions: both 3b and 3c underwent the intramolecular ring closing reaction quantitatively to afford compounds cis-Ru2(D(3,5-Cl2Ph)F)2(mu-O2C(CH2)nCH=CH2(CH2)nCO2)Cl with n=2 (4b) and 3 (4c), respectively, but 3a displayed no metathesis reactivity. Molecular structures of compounds 1a/1b, 2a/2b, 3a/3b, and 4b were established via X-ray diffraction studies, confirming the formation of cross and ring closing metathesis products. Voltammograms of compounds 2 are nearly identical to those of compounds 1, indicating the absence of electronic interactions mediated by the tether derived from olefin metathesis.     

Three new C21 steroidal glycosides from the roots of Cynanchum inamoenum

Three new C_(21) steroidal glycosides named inamoside E (1),inamoside F (2) and inamoside G (3) were isolated from the roots of Cynanchum inamoenum (Maxim.) Loes.Their structures were determined by spectroscopic analysis,especially by 1D and 2D NMR experiments.