Two new flavans from the trunk and leaves of Horsfieldia glabra

Two new flavans, (2R, 4R)-4′-hydroxy-3′,5′-methyl-6,7-methylenedioxy-4-O-2′-cycloflavan (1), and (2R, 4R)-4′-hydroxy-3′-methyl-6,7-methylenedioxy-4-O-2′-cycloflavan (2), along with six known compounds were isolated from the trunk and leaves of Horsfieldia glabra. Their structures were elucidated by means of extensive spectroscopic analysis. Compounds 1 and 2, together with 4–7 were assessed for their cytotoxicity against five human cancer cell lines (HL-60, SMMC-7721, A-549, MCF-7 and SW-480), and the result showed that they had no activity.     

Decarboxylation of α-Amino Acids Containing Two and Three Stereogenic Centers: A Simple One-Step Procedure to Prepare two Optically Active β-Amino Alcohols and a Bicyclic Pyrrolidine Derivative

The decarboxylation of L-threonine (2S,3R)-1, L-hydroxyproline (2S,4R)-2 and D-2-azabicyclo[3.3.0]octan-3-carboxylic acid (1R,3R,5R)-5 yield in a simple one-step procedure the corresponding optically active β-amino alcohols (R)-3 and (R)-4 and the bicyclic pyrrolidine derivative (1R,5R)-6 in 72–82% yield and >99% ee.     

New neolignan glycosides and a new cerebroside from <Emphasis Type="Italic">Symplocos caudata</Emphasis>

A phytochemical investigation of the roots of Symplocos caudata Wall (Symplocaceae) resulted in the isolation and characterization of two optical isomers of a neolignan glycoside (1) and a new cerebroside (2). Their structures were elucidated as (7R,8S)-erythro-7,9,9'-trihydroxy-3,3',5'-trimethoxy-8-O-4'-neolignan-4-O-β-D-glucopyranoside, (7S,8R)-erythro-7,9,9'-trihydroxy-3,3',5'-trimethoxy-8-O-4'-neolignan-4-O-β-Dglucopyranoside (1), and 1-O-β-D-glucopyranosyl-(2S,3S,4R,8Z,12E)-2-N-[(2'R)-2'-hydroxyheptacosanoyl]-8,12-docosadiene-1,3,4-triol (2), respectively, on the basis of spectroscopic data (1D and 2D NMR, MS and CD).     

Two new sesquiterpenes from Chloranthus japonicus Sieb

Two new sesquiterpenes, namely, 1β,10β-dihydroxy-eremophil-7(11), 8-dien-12,8-olide (1) and 8,12-epoxy-1β-hydroxyeudesm-3,7,11-trien-9-one (2), together with three known sesquiterpenoids, shizukolidol (3), 4α-hydroxy-5α(H)-8β-methoxy-eudesm-7(11)-en-12,8-olide (4), and neolitacumone B (5), and two known monoterpenes, (3R,4S,6R)-p-menth-1-en-3,6-diol (6) and (R)-p-menth-1-en-4,7-diol (7), were isolated from the whole plant of Chloranthus japonicus Sieb. Their structures were elucidated on the basis of spectroscopic data analysis and comparison with those of related known compounds. Compounds 4–7 were isolated from this plant for the first time.     

Isolation,structural elucidation and cytotoxicity evaluation of a new pentahydroxy-pimarane diterpenoid along with other chemical constituents from Aerva lanata

Aervalanata possesses various useful medicinal and pharmaceutical activities. Phytochemical investigation of the plant has now led to the isolation of a new 2α,3α,15,16,19-pentahydroxy pimar-8(14)-ene diterpenoid (1) together with 12 other known compounds identified as β-sitosterol (2), β-sitosterol-3-O-β-D-glucoside (3), canthin-6-one (4), 10-hydroxycanthin-6-one (aervine, 5), 10-methoxycanthin-6-one (methylaervine, 6), β-carboline-1-propionic acid (7), 1-O-β-D-glucopyranosyl-(2S,3R,8E)-2-[(2′R)-2-hydroxylpalmitoylamino]-8-octadecene-1,3-diol (8), 1-O-(β-D-glucopyranosyl)-(2S,3S,4R,8Z)-2-[(2′R)-2′-hydroxytetracosanoylamino]-8(Z)-octadene-1,3,4-triol (9), (2S,3S,4R,10E)-2-[(2′R)-2′-hydroxytetracosanoylamino]-10-octadecene-1,3,4-triol (10), 6′-O-(4″-hydroxy-trans-cinnamoyl)-kaempferol-3-O-β-D-glucopyranoside (tribuloside, 11), 3-cinnamoyltribuloside (12) and sulfonoquinovosyldiacylglyceride (13). Among these, six compounds (8–13) are reported for the first time from this plant. Cytotoxicity evaluation of the compounds against five cancer cell lines (CHO, HepG2, HeLa, A-431 and MCF-7) shows promising IC₅₀ values for compounds 4, 6 and 12.     

Enantiomerically pure 7-oxabicylo[2.2.1]hept-5-en-zyl derivatives as synthetic intermediates. Part III. Total synthesis of D- and L-ribose derivatives

Enantiomerically pure methyl 5-bromo-5-deoxy-2,3-O- isopropylidene-β-D - (D - 5b ) and -β-l-ribofuranoside (l- 5b ) have been derived from (?)-(1R,2S,4R)-2-exo-cyano-7-oxabicylo[2.2.1]hept-5-en-endo,-yl (1′S)-camphanate ( 1 ) and (+)-(1S,2R,4S)-2-exo-cyano-7-oxabicyclo[2.2.1]hept-5-en-2-endo-yl(1′R)-camphanate ( 2 ), respectively, in 5 synthetic steps and 28% overall yield. Hydrolysis of D-5b and L - 5b afforded methyl 2,3-O isopropylidene-β-D -ribofuranoside (D -5a) and methyl 2,3-O-isopropylidene β-L-ribofuranoside (L-5a), respectively. The intermediate (+)-(1R,4R,5R,6R) 5-exo,6-exo-(isopropylidenedioxy)- 7 -oxabicyclo[2.2.1]heptan-2-one ((+)- 7 ) and its enantiomer(–)-7 were also obtained enantiomerically pure by resolution of (=)- 7 by the Johnson-Zeller method. In bothe approaches, the chiral auxiliaries ((–)- and (+)-camphanic acids, or (+)-(S)-N,S-dimethyl-S-phenylsulfoximide) were recovered at an early stage of the synthesis.     

Highly Stereoselective Total Syntheses of 2,5-Anhydro-4-deoxy-D-ribo-hexonic Acid and of (1S)-1-C-(6-amino-7H-purin-8-yl)-1,4-anhydro-3-deoxy-D-erythro-pentitol (= cordycepin C)

Highly regio- and stereoselective monohydroxylation of the C?C bond of (+)-7-oxabicyclo[2.2.1]hept-5-en-2-one ( 8 ) was achieved via LiAlH₄ reduction of the corresponding 5,6-exo-epoxy dimethyl acetal 9 . The reaction gave exclusively (–)-(1R, 2R, 4S)-6,6-dimethoxy-7-oxabicyclo[2.2.1]heptan-2-exo-ol ( 10 ) which was transformed into 2,5-anhydro-3-O-benzyl-4-deoxy-D -ribo-hexonic acid ( 15 ) and 2,5-anhydro-4-deoxy-D -ribo-hexonic acid ( 6 ) via ozonolysis of (–)-(1R, 4S, 6R)-6-exo-benzyloxy-2-{[(tert-butyl)dimethylsilyl]oxy}-7-oxabicyclo[2.2.1]hept-2-ene ( 14 ). Cordycepin C ( 5 ) was derived from 6 and 4,5,6-triaminopyrimidine using CsF/DMF to generate the adenine heterocycle.     

New flavonoid glycosides and other chemical constituents from Clerodendrum phlomidis leaves: isolation and characterisation

Phytochemical investigation of the plant Clerodendrum phlomidis Linn. F. (Lamiaceae) has now led to the isolation of two new flavonoid glycosides (1, 2) together with six known compounds identified as pectolinaringenin (3), pectolinaringenin-7-O-β-d-glucopyranoside (4), 24β-ethylcholesta-5,22E,25-triene-3β-ol (5), 24β-ethylcholesta-5,22E,25-triene-3β-O-β-D-glucopyranoside (6), (2S,3S,4R,10E)-2-[(2′R)-2′-hydroxytetracosanoylamino]-10-octadecene-1,3,4-triol (7) and andrographolide (8) mainly by spectroscopic analysis. Compounds 4 and 6–8 are reported for the first time from C. phlomidis.     

Chemical constituents and biological activities of Viburnum macrocephalum f. keteleeri

Three new compounds (1–3) and seven known compounds (4–10) have been isolated from the ethanolic extract of Viburnum macrocephalum f. keteleeri using bioactivity-guided fractionation and identified as methyl (2-α-L-rhamnopyranosyloxy)acetate (1), methyl (2R-3-α-L-rhamnopyranosyloxy)glycerate (2), methyl (3R-4-α-L-rhamnopyranosyloxy-3-hydroxy)butanoate (3), bridelionoside B (4), (6S,7E,9R)-roseoside (5), linarionoside A (6), 3,7,11-trimethyl-1,6-dodecadien-3,10,11-triol (7), (+)-8-hydroxylinalool (8), β-sitosterol (9) and daucosterol (10). The structures of 1–3, including absolute configurations, were determined by spectroscopic data (¹H and ¹³C NMR, HSQC, HMBC and ORD) and chemical methods. In addition, compounds 1–8 were assayed for their insecticidal and antimicrobial activities. Compounds 7 and 8 exhibited moderately insecticidal effects against Mythimna separata with LD₅₀ values of 180 and 230 μg g^?1, respectively. Compounds 2, 3, 7 and 8 showed varying antimicrobial activities with IC₅₀ values ranging from 125 to 529 μM.     

A new curvularin glycoside and its cytotoxic and antibacterial analogues from marine actinomycete Pseudonocardia sp. HS7

Five curvularin macrolides (1–5) were isolated from the cultured broth of marine actinomycete Pseudonocardia sp. HS7 that was obtained from the cloacal aperture of sea cucumber Holothuria moebii. The structures of these isolates were characterized as (11S,15R)-11-hydroxycurvularin (1), (11R,15R)-11-hydroxycurvularin (2), curvularin-7-O-α-D-glucopyranoside (3), trans-dehydrocurvularin (4) and curvularin (5) based on their NMR and HRESIMS data as well as chemical degradation. Compound 3 is a new macrolide with a rare α-D-glucopyranose substituent. Compounds 1–4, 5a and 5c (the acyl products of 5), suppressed the proliferation of all six tested cancer cell lines and 4 is the most active compound with IC₅₀ values ranging from 0.59 to 3.39 μM. The 11-hydroxycurvularins 1 and 2 also showed antibacterial activity inhibiting the growth of Escherichia coli.     

Antiangiogenic phenylpropanoid glycosides from Gynura cusimbua

A new phenylpropanoid glycoside, named α-L-rhamnopyranosyl-(1?2)-β-D-[4″-(8E)-7-(3,4-dihydroxyphenyl)-8-propenoate, 1″-O-(7S)-7-(3,4-dihydroxyphenyl)-7-methoxy-ethyl]-glucopyranoside (1), together with nine known compounds (2–10) were isolated from the active fraction (n-Butanol fraction) of Gynura cusimbua for the first time. The known compounds (2–10) were identified as phenylpropanoid glycosides on the basis of extensive spectral data and references. The antiangiogenic activities of compounds (1–10) were evaluated by MTT assay on HUVECs and wild-type zebrafish in vivo model assay. As a result, compounds 1, 6, 7, 8 and 10 exhibited certain antiangiogenic activities.     

A new epicatechin glucopyranoside derivative from Styrax suberifolius

Abstract

A new derivative of epicatechin glucopyranoside, (2R,3R)-3,7,4'-trihydroxy-5,3'-dimethoxyflavan 7-O-β-d-glucopyranoside (1), together with three mononuclear phenolic acid esters, methyl orsellinate (2), ethyl orsellinate (3) and methyl β-orcinolcarboxylate (4) were isolated from the bark of Styrax suberifolius. The structures of 1–4 were determined on the basis of extensive analysis of NMR and MS spectra combined with chemical hydrolysis. The antifungal activities of the isolated compounds against three plant pathogenic fungi, Alternaria solani, Fusarium oxysporum and Phomopsis cytospore were evaluated using radial growth inhibition assay. Compounds 2, 3 and 4 exerted selective inhibitory activities against the tested fungi. Among of them, methyl β-orcinolcarboxylate (4) exhibited obvious inhibitory effect against P. cytospore, with an inhibition rate of 86.72% at 100?μg/ml.     

Synthesis and investigation of antibacterial activities and carbonic anhydrase and acetyl cholinesterase inhibition profiles of novel 4,5-dihydropyrazol and pyrazolyl-thiazole derivatives containing methanoisoindol-1,3-dion unit

Novel 4,5-dihydropyrazole derivatives (3a–i), 3-(4-((3aR,4S,7R,7aS)-1,3-dioxo-3a,4,7,7a-tetrahydro-1H-4,7-methanoisoindol-2(3H)-yl)phenyl)-5-phenyl-4,5-dihydro-1H-pyrazole-1-carbothio amide, were obtained by the addition of thiosemicarbazide (2) to the chalcones (1a–i). The addition–cyclization of 2,4′-dibromoacetophenone (4) to pyrazole derivatives (3a–i) gave the new pyrazolyl-thiazole derivatives (5a–i), (3aR,4S,7R,7aS)-2-(4-(1-(4-(4-bromophenyl)thiazol-2-yl)-5-phenyl-4,5-dihydro-1H-pyrazol-3-yl)phenyl)-3a,4,7,7a-tetrahydro-1H-4,7-methanoisoindole-1,3(2H)-dione. Antibacterial and acetylcholinesterase (AChE) enzyme and human carbonic anhydrase (hCA) I, and II isoform inhibitory activities of the compounds 3a–i and 5a–i were investigated. Some of the compounds showed promising antibacterial activity. In addition, the hCA II and I were effectively inhibited by the lately synthesized derivatives, with K_i values in the range of 18.90?±?2.37 ?58.25?±?13.62?nM for hCA II and 5.72?±?0.98 ?37.67?±?5.54?nM for hCA I. Also, the K_i parameters of these compounds for AChE were obtained in the range of 25.47?±?11.11???255.74?±?82.20?nM. Also, acetazolamide, clinical molecule, was used as a CA standard inhibitor that showed K_i value of 70.55?±?12.30?nM against hCA II, and 67.17?±?9.1?nM against hCA I, and tacrine inhibited AChE showed K_i value of 263.67?±?91.95.     

SYNTHESIS OF ANELLATED ANHYDROPYRANOSES ON THE BASIS OF 1,6-ANHYDRO-3-DEOXY-4-METHYLSULFANYL-3-[(METHYLSULFANYL)METHYLENE]-β-D-ERYTHRO-HEXOPYRANOS-2-ULOSE

(Z)-1,6-Anhydro-3-deoxy-4-methylsulfanyl-3-[(methylsulfanyl)methylene]-β-D-erythro-hexopyranos-2-ulose (1) reacted with diethyl malonate, 1,3-diketones, N-aryl-3-oxobutyramides and dialkyl 3-oxoglutarate, respectively, in the presence of potassium carbonate and crown ether to yield diethyl 2-(1,6-anhydro-4-methylsulfanyl—D-arabino-hex-2-ulopyranos-3-ylmethylene) malonate (2), 1-{(1R,2S,8S,9R)-2-hydroxy-4-methyl-8-methylthio-3,11,12- trioxatricyclo7.2.1.0^2,7dodeca-4,6-dien-5-yl} ethanone (3), (1R,2S,12S,13R)-2-hydroxy-12-methylthio-3,15,16-trioxatetracyclo[11.2.1. 0^2,11. 0^4,9] hexadeca- 4(9),10-dien-8-one (4), (1R,8S,9R)-5-acetyl-3-aryl-8-methylthio-11,12-dioxa- 3-azatricyclo-[7.2.1.0^2,7]dodeca-2(7),5-dien-4-ones (5,6) and dialkyl (1R,8S,-9R)-4-hydroxy-8-methylthio-11,12-dioxatricyclo[7.2.1.0^2,7]dodeca-2(7),3,5-triene-3,5-dicarboxylates (7,8), respectively.     

Asymmetric synthesis of (S,R)- and (R,R)-methiin stereoisomers

Abstract

An asymmetric synthesis of (+)- and (–)-methiine (S-methyl-(R)-cysteine sulfoxide) diastereomers has been developed. These natural sulfur compounds were isolated from a variety of Brassica vegetables. As the starting compound, (R)-cysteine was used, which was methylated to form (R)-S-methylcysteine. Then the oxidation of S-methylcysteine with tert-butyl hydroperoxide catalyzed by the chiral tetra(isopropylate)titanium/(S)- or (R)-Binol complex led to the formation of (1?R,2S)-(+)- or (1?R,2R)-(–)-methiin stereomers.     

A new ceramide from the root of <Emphasis Type="Italic">Isatis Indigotica</Emphasis> and its cytotoxic activity

In addition to two ceramides 1-O-β-D-glucopyranosyl-(2S,3R)-N-(2'-hydroxyhexadecanoyl)-octadeca-4E,8Esphingenine (2) and (2S,3S,4R)-N-(2'-hydroxytetracosanoyl)-octadecasphingenine (3), which separated for the first time, a new ceramide 1-O-β-D-glucopyranosyl-(2S,3R)-N-(2'-hydroxyhexacosanoyl)octadecasphingenine (1) was isolated from the traditional Chinese medicinal herb Isatis indigotica. Their cytotoxic effects were evaluated by the MTT method.     

Enantioselective fluorescent recognition of mandelate by substituted BINOL in aqueous solutions

The fluorescent photo-induced electron transfer chemosensors (R)-1, (R)-2, (S)-1 and (S)-2 based on the 3,3′-positions of 1,1′-bi-2-naphthol were designed for their recognition of mandelate. The binding properties for mandelate were examined by the fluorescence spectra. The high fluorescence sensitivity and enantioselectivity make compound (R)-2 a practically useful sensor for the recognition of mandelate in CH₃OH/H₂O system (1:1, 0.01 M Tris–HCl buffer, pH 7.4).     

Neue Phellandren-Derivate aus dem Wurzelöl von Angelica archangelicaL

New Phellandrene Derivatives from the Root Oil of Angelica archangelica L . 2-Nitro-1,5-p-menthadiene ( 5 ), trans- and cis-6-nitro-1(7), 2-p-menthadiene ( 6 and 7 ), trans-1(7), 5-p-menthadien-2-yl acetate ( 9 ) and a formal phellandrene derivative, 7-isopropyl-5-methyl-5-bicyclo [2.2.2]octen-2-one ( 16 ), have been identified in the root oil of Angelica archangelica L . Starting from (?)-(R)-α-phellandrene ( 1 ) (R)- 5 , (4R, 6S)- 6 /(4R, 6R)- 7 , (2S, 4R)- 9 and (1R, 4R, 7R)- 16 as well as (2S, 4R)- 11 , (2R, 4R)- 12 and (2R, 4R)- 10 have been prepared.     

Hepatoprotective phenylethanoid glycosides from Cirsium setosum

Two new phenylethanoid glycosides, namely β-D-glucopyranoside, 1″-O-(7S)-7-(3-methoxyl-4-hydroxyphenyl)-7-methoxyethyl-3″-α-L-rhamnopyranosyl-4″-[(8E)-7-(3-methoxyl-4-hydroxyphenyl)-8-propenoate] (1) and β-D-glucopyranoside, 1″-O-(7S)-7-(3-methoxyl-4-hydroxyphenyl)-7-methoxyethyl-3″-α-L-rhamnopyranosyl-4″-[(8E)-7-(4-hydroxyphenyl)-8-propenoate] (2), together with six phenylethanoid glycosides were isolated from Cirsium setosum. Their structures were elucidated by their spectroscopic data and references. Compounds 2, 4, 5, 7 and 8 (10 μM) exhibited moderate hepatoprotective activities. Compounds (3–8) were obtained from this plant for the first time.     

Pleiocarpumlignan A,a new dineolignan from Piper pleiocarpum Chang ex Tseng

Abstract

The investigation of chemical constituents from the whole plants Piper pleiocarpum Chang ex Tseng resulted in the isolation of one new dineolignan, pleiocarpumlignan A (1), along with one known benzoate derivative, trans-2,3-diacetoxy-1-[(benzoy1oxy)methyl]-cyclohexa-4,6-diene (2), and two known neolignans (3–4) as (±)-trans-dehydrodiisoeugenol (3), (7R,8R,3′S)-△^8′-3′,6′-dihydro-3′-methoxy-3,4-methylenedioxy-6′-oxo-8,3′,7,O,4′-lignan (4). Their structures were elucidated through extensive spectroscopic analyses including 1D, 2D NMR, HR-ESI-MS, and by comparison with the literature. All compounds (1–4) were firstly isolated from Piper pleiocarpum Chang ex Tseng. The ¹³C NMR spectra of 2 were completely assigned for the first time. Cytotoxic activities of these isolated compounds against five human cancer cell lines (including A-549, SMMC-7721, HL-60, MCF-7, and SW-480) were evaluated.