Showing papers in "Chemical & Pharmaceutical Bulletin in 1987"
TL;DR: In this paper, pairs of enantiomers of nine aldoses were separated by gas-liquid chromatography on an OV-17 capillary column as the trimethylsilyl ethers of methyl 2- (polyhydroxyalkyl) -thiazolidine-4 (R) -carboxylates.
Abstract: Pairs of enantiomers of nine aldoses were separated by gas-liquid chromatography on an OV-17 capillary column as the trimethylsilyl ethers of methyl 2- (polyhydroxyalkyl) -thiazolidine-4 (R) -carboxylates, which were obtained by the reaction of aldoses with L-cysteine methyl ester. This method was applied to the determination of the absolute configurations of the component monosaccharides of a Thladiantha saponin.
530 citations
TL;DR: A new phenolic glycoside, icariside A1 (IV), and six terpenic glycosides have been isolated from Epimedium grandiflorum MORR. var. thunbergianum (MIQ.) NAKAI as discussed by the authors.
Abstract: A new phenolic glycoside, icariside A1 (IV), and six new terpenic glycosides, icariside B1 (V), B2 (VI), C1 (VII), C2 (VIII), C3 (IX), and C4 (X), have been isolated from Epimedium grandiflorum MORR. var. thunbergianum (MIQ.) NAKAI, together with three known glycosides, salidroside (I), thalictoside (II) and benzyl glucoside (III). The structures of IV-X were established on the basis of chemical evidence and spectral data.
263 citations
TL;DR: In this paper, the diffusion coefficients of several model compounds having molecular weights ranging from 122 to 1050 were estimated as a function of the polymer concentration in the fully-cured beads.
Abstract: Calcium-induced alginate gelation was examined in terms of water content changes. The gelation was accompanied with considerable water loss, which reached about 50-60% (w/w) reduction in the fully-cured state. The calcium association with the polymer was strong enough to maintain the shape of fully-cured beads in distilled water and the amount of the ions associated with the alginate used in the present study was 1.6 × 10 -3mol/g of polymer. The diffusion coefficients of several model compounds having molecular weights ranging from 122 to 1050 were estimated as a function of the polymer concentration in the fully-cured beads.The swelling property of dried gel particles prepared from fully-cured hydrogels was of interest : the particles remained unchanged in distilled water or acidic medium (pH 1.5 KCl-HCl) but swelled rather rapidly in pH 7.0 phosphate buffer to a size greater than their original size before being dried. Such a pH-sensitive swelling property could be advantageous for orally-administered drug vehicles, especially when an acid-sensitive drug is incorporated in the gel.
147 citations
TL;DR: In this paper, a chiral recognition column with conjugated ovomucoid as the ligand was developed for chiral resolution of acids as well as amines without derivatization.
Abstract: A new chiral recognition column, with conjugated ovomucoid as the ligand, was developed. This column may be employed for the chiral resolution of acids as well as amines without derivatization. The retention time, capacity factor and resolution factor were dependent on pH, buffer strength and 2-propanol concentration of the mobile phase. For chlorpheniramine, a resolution factor of 1.5 was obtained.
143 citations
TL;DR: Two new isoflavone glycosides, the 8-C-apiosyl (1→6) glucosides of daidzein and genistein, were isolated from the roots and the voluble stems of Pueraria lobata (WILLD.) OHWI as mentioned in this paper.
Abstract: Two new isoflavone glycosides, the 8-C-apiosyl (1→6) glucosides of daidzein and genistein, were isolated from the roots and the voluble stems of Pueraria lobata (WILLD.) OHWI. Thirteen known isoflavonoids and related compounds were also found.
133 citations
TL;DR: Seven long-chain phenols were isolated from Ginkgo biloba L and three of them, anacardic acid, bilobol, and cardanol, showed antitumor activity against Sarcoma 180 ascites in mice.
Abstract: Seven long-chain phenols were isolated from Ginkgo biloba L. Three of them, anacardic acid (Ib), bilobol (IIa), and cardanol (IIIa), showed antitumor activity against Sarcoma 180 ascites in mice. The antitumor effectiveness was rated (+ +) for Ib, (+ + +) for IIa, and (+ + +) for IIIa at 40 mg/kg/d by the total packed cell volume method.
115 citations
TL;DR: Two optically active (100% enantiomeric excess) isomers of ofloxacin (1) and its fluoromethyl derivative (2) were approximately twice as active as the corresponding racemates, while the (+) -isomers were considerably less active than the Racemates.
Abstract: Two optically active (100% enantiomeric excess) isomers (13a and 13b) of ofloxacin (1) [(±) -ofloxacin; DL-8280; (±) -9-fluoro-2, 3-dihydro-3-methyl-10- (4-methyl-1-piperazinyl) -7-oxo-7H-pyrido [1, 2, 3-de] [1, 4] benzoxazine-6-carboxylic acid] and their fluoromethyl derivatives (14a and 14b) were prepared via their optically active intermediates resolved by use of high-performance liquid chromatography (HPLC). The isomers (13a and 13b) were also obtained efficiently by an alternative route via separation of the diastereoisomers (18, 19) prepared in the reaction of benzoxazine (17) with L-prolinyl chloride.The (-) -isomers of 1 and its fluoromethyl derivative (2) were approximately twice as active as the corresponding racemates, while the (+) -isomers were considerably less active than the racemates.The absolute configuration at the C3 position in the oxazine ring in a series of (-) -compounds (b) was confirmed by X-ray analysis of the hydrochloride of the (-) -benzoxazine derivative (15b) to be S.
110 citations
TL;DR: Results indicate that the major chain of Grifola frondosa is made up of β-1, 6-linked glucose residues with branches of β, 3- linked glucose, and this glucan inhibited the growth of Sarcoma 180 tumor in ICR mice.
Abstract: A polysaccharide was extracted from fruit bodies of Grifola frondosa (maitake), and the chemical structure and antitumor activity were studied. The extracted polysaccharide could be hydrolyzed by ?A-glucanase into glucose, indicating it to be a β-glucan. The sample gave methyl 2, 3, 4, 6- tetra-Ο-, methyl 2, 4, 646-Ο-, methyl 2, 3, 4-tri -Ο- and methyl 2, 4-di-Ο-methylglucoside in the molar ratio of 4 : 2 : 1 : 4 on methylation. In the carbon-13 nuclear magnetic resonance spectrum, the signals of C-6' (related to (1-6) bonding) and C-3' (related to (1-3) bonding) were observed in addition to those of free C-6 and C-3. These results indicate that the major chain is made up of β-1, 6-linked glucose residues with branches of β-1, 3-linked glucose. This glucan inhibited the growth of Sarcoma 180 tumor in ICR mice.
101 citations
TL;DR: The active principles, A-3 and B-1, were fractionated and purified from the EtOH extract of red-mold rice prepared with Monascus pilosus through extraction with H2O, Amberlite CG-120 column chromatographies and high-performance liquid chromatography on an ODS column.
Abstract: During an initial search for pharmacologically active principles in red-mold rice, two hypotensive compounds were isolated and identified. The active principles, A-3 and B-1, were fractionated and purified from the EtOH extract of red-mold rice prepared with Monascus pilosus through extraction with H2O, Amberlite CG-120 column chromatographies and high-performance liquid chromatography on an ODS column. A-3 was identified as acetylcholine chloride by comparison with an authentic sample, and B-1, colorless needles of mp 203-205 °C, was proved to be identical with authentic γ-aminobutyric acid. Intravenously administered A-3 (0.5 μg/kg) and B-1 (250μg/kg) produced potent depression of the carotid arterial blood pressure in spontaneously hypotensive rats, as did the corresponding authentic samples.
98 citations
TL;DR: In this article, five diarylheptanoids including two new compounds were isolated from the rhizomes of Curcuma xanthorrhiza (Zingiberaceae).
Abstract: Five diarylheptanoids including two new compounds were isolated from the rhizomes of Curcuma xanthorrhiza (Zingiberaceae). The structures of the new compounds were determined to be octahydrocurcumin ((3S, 5S) -1, 7-bis (4-hydroxy-3-methoxyphenyl) -heptane-3, 5-diol) (Ia) and (1ξ) -1-hydroxy-1, 7-bis (4-hydroxy-3-methoxyphenyl) -6-heptene-3, 5-dione (II) on the basis of spectral and chemical evidence.The absolute configurations of Ia and a new similar diarylheptanoid, (3R, 5R) -1- (4-hydroxyphenyl) -7-phenylheptane-3, 5-diol (VIa), isolated from the rhizomes of Alpinia officinarum (Zingiberaceae), were established by application of the exciton chirality rule.
97 citations
TL;DR: It seems to be essential for marked antitumor activity that ellagitannins should possess a dimeric structure with several galloyl groups on the glucose core.
Abstract: Sixty-three tannins and related polyphenols were intraperitoneally injected into mice at 4 d before intraperitoneal sarcoma-180 cell inoculation, and their antitumor activities were evaluated. The condensed tannins and related compounds all showed negligible activity. As regards the hydrolyzable tannins, active compounds were found among ellagitannins. In particular, dimeric ellagitannins such as oenothein B, rugosin E, rugosin D, gemin A and coriariin A showed significantly higher antitumor activity than agrimoniin, which we previously reported as an antitumor tannin. Coriariin A, which has four galloyl groups instead of two hexahydroxydiphenoyl groups of agrimoniin, showed the strongest activity. It seems to be essential for marked antitumor activity that ellagitannins should possess a dimeric structure with several galloyl groups on the glucose core.
TL;DR: Two new lignans, erythro-dihydroxydehydrodiconiferyl alcohol (1) and its threo isomer (2), were isolated from the bark of Eucommia ulmoides OLIV as mentioned in this paper.
Abstract: Two new lignans, erythro-dihydroxydehydrodiconiferyl alcohol (1) and its threo isomer (2), were isolated from the bark of Eucommia ulmoides OLIV. (Eucommiaceae), together with six known lignans and three known phenolic compounds. Their structures were elucidated on the basis of spectroscopic analyses and chemical evidence.
TL;DR: In this paper, four new phenylethanoid glycosides, tubulosides A (II), B (VI), C (VII) and D (VIII), have been isolated from Cistanche tubulosa (SCHRENK) hook.
Abstract: Four new phenylethanoid glycosides, tubulosides A (II), B (VI), C (VII) and D (VIII), have been isolated from Cistanche tubulosa (SCHRENK) HOOK. f. (Orobanchaceae), together with four known phenylethanoid glycosides, echinacoside (I), acteoside (III), acteoside isomer (IV) and 2'-acetylacteoside (V). The structures of II, VI, VII and VIII were established on the basis of chemical evidence and spectral data. Compounds VII and VIII possess a triacetylrhamnosyl moiety as the terminal sugar.
Journal Article•
TL;DR: In this paper, the reactivity of phthalimide-Noxyl radical (2) produced by an electrochemical one-electron oxidation of N-hydroxyphthalimide (1) was investigated.
Abstract: The reactivity of phthalimide-N-oxyl radical (2), which is produced by an electrochemical one-electron oxidation of N-hydroxyphthalimide (1), was investigated. The self-decomposition of 2 obeyed second-order kinetics with respect to itself and the rate was little affected by changing the temperature or the concentration of dissolved oxygen, water or added base. In the reaction between 2 and benzhydrol or its α-deuterated derivative, the decay of the radical was first-order with respect to each component. The observed large deuterium isotope effect (kH/kD= 10.6 at 25 °C) is attributed to the rate-limiting hydrogen abstraction. Rate measurements were performed on the reaction with 24 other substrates which have one or more hydrogen atoms on a benzylic or allylic position or on a carbon adjacent to a hetero atom.
TL;DR: Trimethylsilyl bromide in trifluoroacetic acid was found to have the ability to cleave benzyl-type protecting groups, i.e., benzyloxycarbonyl (Z), benzyl (O-Bzl) and p-methoxybenzyl (S-MBzl).
Abstract: Trimethylsilyl bromide (TMSBr) in trifluoroacetic acid (TFA) was found to have the ability to cleave benzyl-type protecting groups, i.e., benzyloxycarbonyl (Z), benzyl (O-Bzl) and p-methoxybenzyl (S-MBzl). The reaction was best accelerated by addition of thioanisole, compared with other soft nucleophiles so far examined. The rate of the cleavage reaction with TMSBr/TFA was judged to be somewhat slower than that with trimethylsilyl trifluoromethanesulfonate/TFA. However, TMSBr/TFA reduced Met(O) efficiently and gave almost no side reaction of Asp (succinimide formation). This deprotecting procedure was applied to the synthesis of human gastrin-releasing peptide.
TL;DR: The acid-catalyzed rearrangement of triterpenoid monoenes belonging to the hopane and migrated hopane series with sulfuric acid and boron trifluoride etherate was investigated in this paper.
Abstract: The acid-catalyzed rearrangement of triterpenoid monoenes belonging to the hopane and migrated hopane series with sulfuric acid and boron trifluoride etherate was investigated. By selecting the reaction conditions, a variety of the monoenes of these series, including three new compounds, 9βH-fern-7-ene (3c), 8βH-fern-9 (11) -ene (4b), and adian-5 (10) -ene (5b), were obtained. For comparison, oleanenes and migrated oleanenes were also subjected to the same reaction.
TL;DR: In this article, the absolute configurations of sappanol, episappanol, methylepisappanol and methylbrazilin were determined by means of Horeau's partial resolution method and chemical correlations.
Abstract: Three new phenolic compounds, 3'-Ο-methylsappanol, 3'-Ο-methylepisappanol and 3'-Ο-methylbrazilin, were isolated from Sappan Lignum, the dried heartwood of Caesalpinia sappan. The absolute configurations of sappanol, episappanol, 3'-deoxysappanol, 3'-Ο-methylsappanol, 3'-Ο-methylepisappanol, brazilin and 3'-Ο-methylbrazilin were determined by means of Horeau's partial resolution method and chemical correlations.Sappanol, episappanol, 3'-deoxysappanol, 3'-Ο-methylsappanol and 3'-Ο-methylepisappanol form a novel class of homoisoflavonoids.
TL;DR: Thallium (III) trifluoroacetate, a mild oxidant with a soft-acid character, was found to cleave various S-protecting groups of cysteine in tr ifluoroacetic acid, with spontaneous formation of cystine.
Abstract: Thallium (III) trifluoroacetate, a mild oxidant with a soft-acid character, was found to cleave various S-protecting groups of cysteine in trifluoroacetic acid, with spontaneous formation of cystine Except for unmasked Trp and Met, other amino acids, including His and Tyr, remained intact in the presence of this oxidant The usefulness of this oxidant for intramolecular disulfide bond-forming reactions was demonstrated by direct conversion of three model S-protected cysteine-peptides into cystine-peptides, ie, oxytocin, urotensin II and human calcitonin generelated peptide
TL;DR: In this paper, three new sesquiterpenes, isozedoarondiol (8), methylzedoarondions (9) and neocurdione (10), were isolated along with germacrone (1), curdione (2), (4S, 5S) -germacrone 4, 5-epoxide (3), dehydrocurdione(4), procurcumenol (5), zedoarONDiol (6), and curcumenone (7) from Curcuma aromatica SALISB.
Abstract: Three new sesquiterpenes, isozedoarondiol (8), methylzedoarondiol (9) and neocurdione (10), were isolated along with germacrone (1), curdione (2), (4S, 5S) -germacrone 4, 5-epoxide (3), dehydrocurdione (4), procurcumenol (5), zedoarondiol (6) and curcumenone (7) from Curcuma aromatica SALISB. The absolute configuration of 6 was determined by X-ray analysis and chemical correlation with 3. The structures of 8, 9 and 10 were also determined.
TL;DR: In this paper, a new flavanone glucoside, named andrographidine A (1), and five new glucosides (andrographidines B (2), C (3), D (4), E (5) and F (6), were isolated from the root of Andrographis paniculata.
Abstract: A new flavanone glucoside, named andrographidine A (1), and five new flavone glucosides, named andrographidines B (2), C (3), D (4), E (5) and F (6), were isolated from the root of Andrographis paniculata. Their structures were determined on the basis of spectral data, especially carbon-13 and proton nuclear magnetic resonance spectra, and chemical derivatization. They have uncommon O-substitution patterns involving 5-, 7-, 8-, 2'-, 3'-and 4'-O-substituents.
TL;DR: Percutaneous application of diclofenac in the aqueous gel form, prepared with phospholipid, may be available for topical treatment rather than for systemic treatment.
Abstract: Poor penetration of diclofenac through in vitro rat dorsal skin including subcutaneous tissue was observed. The poor penetration of diclofenac seemed to be predominantly due to the poor permeability of the stratum corneum. Hydrogenated soya phospholipids (phospholipid) in aqueous gel form increased the penetration of diclofenac in the in vitro study, by increasing diclofenac transport through the stratum corneum. In the in vivo percutaneous absorption of diclofenac, the presence of phospholipid in aqueous gel form increased both plasma diclofenac concentration and diclofenac accumulation in the dorsal skin tissue, including subcutaneous tissue. Since a marked accumulation of diclofenac in the subcutaneous tissue after application of the aqueous gel was observed both in vivo and in vitro, percutaneous application of diclofenac in the aqueous gel form, prepared with phospholipid, may be available for topical treatment rather than for systemic treatment.
TL;DR: In this article, a chemical examination of the aqueous acetone extract of commercial oolong tea has led to the isolation of four new acylated flavan-3-ols 1-4, together with the known compounds 5-13.
Abstract: A chemical examination of the aqueous acetone extract of commercial oolong tea has led to the isolation of four new acylated flavan-3-ols 1-4, together with the known compounds 5-13. On the basis of chemical and spectroscopic evidence, compounds 1-4 have been characterized as (-) - epiafzelechin 3-Ο-gallate (1), (-) -epicatechin 3-Ο- (4-Ο-methyl) -gallate (2), (-) -epicatechin 3-Ο-p-hydroxybenzoate (3) and (-) -epigallocatechin 3-Ο-cinnamate (4).
TL;DR: Pregnenolone, coniferylferulate and nine monoand dihydroxyphthalide derivatives (5-13) were isolated from the commercial C. officinale rhizome as mentioned in this paper.
Abstract: Pregnenolone (1), coniferylferulate (2) and nine monoand dihydroxyphthalide derivatives (5-13) were isolated from the commercial C. officinale rhizome. Their structures were determined from the spectroscopic data and the dihydroxyphthalides senkyunolide-H (11) and -1 (12) and senkyunolide-J (13) were synthesized from the major components ligustilide (14) and senkyunolideA (16), respectively. These oxygenated phthalides were absent in the fresh C. officinale rhizome and they were shown to be derived from the major volatile phthalides during storage of the crude drug . Coniferylferulate (2) also decomposes partly during storage, giving ferulic acid.
TL;DR: Determination of the larvicidal activities of fatty acids and aliphatic alcohols with various alkyl chain lengths, and of analogous compounds with various functional groups, suggested that the balance between hydrophilicity and hydrophobicity is important for the larVicidal activity.
Abstract: Larvicidal principles obtained from the 50% aqueous acetone extract of betel nuts (Areca catechu) were revealed to be a mixture of fatty acids. They were identified by GC-MS analysis as lauric, myristic, palmitic, and oleic acids. Determination of the larvicidal activities of fatty acids and aliphatic alcohols with various alkyl chain lengths, and of analogous compounds with various functional groups, suggested that the balance between hydrophilicity and hydrophobicity is important for the larvicidal activity.
TL;DR: The adsorption of various drugs on microcrystalline cellulose (MCC) suspended in aqueous solutions was investigated in this article, and the adsorability of those drugs on MCC was in the order acrinol>>chlorpromazine>triflupromazine>promazine.
Abstract: The adsorption of various drugs on microcrystalline cellulose (MCC) suspended in aqueous solutions was investigated. Adsorption of diphenhydramine, chlorpheniramine, isoniazid, and p-aminobenzoic acid was very slight or negligible, whereas the adsorption of four phenothiazine derivatives (PTZs) was considerable, and that of acrinol was quite large. Except for chlorpromazine sulfoxide, adsorption isotherms for three PTZs and acrinol were all of the Freundlich type. Based on the Freundlich constants, k and 1/n, the adsorbability of those drugs on MCC was in the order acrinol>>chlorpromazine>triflupromazine>promazine. The slight differences in 1/n for those drugs suggest differences in the adsorption mechanisms. Further it was observed that the adsorption increases with increase of pH, and decreases with increase of ionic strength. In addition, the pH values for MCC suspended solutions decrease gradually with the addition of neutral salts. Thus, in the adsorption of PTZs and acrinol on MCC, the ion-exchange mechanism appeared to play an important role, but adsorption due to non-electrostatic forces should also be appreciable. Marked adsorption of acrinol on MCC can be interpreted in terms of the presence of polar groups capable of hydrogen-bond formation, and the coplanar arrangement of the acridine ring.
TL;DR: In this paper, a chemical examination of the seed shells of Aesculus hippocastanum L. has led to the isolation of proanthocyanidins A-6 (10) and A-7 (11), and aesculitannins A (12), B (13), C (14), D (15), E (16), F (17) and G (18).
Abstract: A chemical examination of the seed shells of Aesculus hippocastanum L. has led to the isolation of proanthocyanidins A-6 (10) and A-7 (11), and aesculitannins A (12), B (13), C (14), D (15), E (16), F (17) and G (18). On the basis of chemical and spectroscopic evidence, proanthocyanidins A-6 (10) and A-7 (11) have been determined to be A-type dimers each possessing a C-4, C-6 interflavanoid linkage, while aesculitannins A (12), B (13), C (14), D (15), E (16), F (17) and G (18) have been characterized as oligomeric proanthocyanidins possessing A-type unit (s) in each molecule. In addition, the presence of (-) -epicatechin (1), proanthocyanidins B-2 (2), B-5 (3), A-2 (4), A-4 (5) and C-1 (6), epicatechin- (4β → 6) -epicatechin- (4β → 6) -epicatechin (7), and cinnamtannins B1 (8) and B2 (9) was also demonstrated.
TL;DR: From the leaves of Thujopsis dolabrata SIEB. as discussed by the authors, four new flavanonol glycosides, the 3-O-β-D-xylopyranosides (1→4) of (+) -taxifolin, (-)-taxifoline, (+)-epitaxifolin and (-) -epitaxisifolin were isolated and their chemical structures were characterized by spectroscopic and chemical investigations.
Abstract: From the leaves of Thujopsis dolabrata SIEB. et Zucc. (Cupressaceae), four new flavanonol glycosides, the 3-O-β-D-xylopyranosides (1→4) of (+) -taxifolin, (-) -taxifolin, (+) -epitaxifolin and (-) -epitaxifolin, together with (+) -catechin (5), (-) -epicatechin (6) and thirteen oligomeric procyanidins (7-19), were isolated and their chemical structures were characterized by spectroscopic and chemical investigations.