Abstract:
:Self-organizing map (SOM) of Kohonen seems to be a promising approach beyond the standard one to regression for some classification problems encountered in the field of pharmacy. We apply them, therefore, to the quantitative structure-activity relationship (QSAR) in carboquinones and benzodiazepines, and show their usefulness. Most QSAR analysis using neural networks has been made by adopting neural networks with supervised learning. On the contrary, SOM obeys unsupervised learning and originally does not involve the use of desired target data. If we note that an appreciable fraction of data may be missing without making the similarity comparison impossible in SOM if the number of attributes considered is appreciable, QSAR analysis using SOM is found to be possible as if supervised learning. Similar to target data in supervised learning, we can take into account target data (=observed activity) as one of attributes in addition to other attributes (=structural descriptors). Choice of optimal descriptors as input parameters was found to be essential to generate valuable SOM.
journal_name
Chem Pharm Bull (Tokyo)journal_title
Chemical & pharmaceutical bulletinauthors
Kawakami J,Hoshi K,Ishiyama A,Miyagishima S,Sato Kdoi
10.1248/cpb.52.751subject
Has Abstractpub_date
2004-06-01 00:00:00pages
751-5issue
6eissn
0009-2363issn
1347-5223journal_volume
52pub_type
杂志文章abstract::Seventeen saponins isolated from the root of Pulsatilla koreana were examined for their in vitro cytotoxic activity against the human solid cancer cell lines, A-549, SK-OV-3, SK-MEL-2, and HCT15, using the SRB assay method, and their in vivo antitumor activity using BDF1 mice bearing Lewis lung carcinoma (LLC). The sa...
journal_title:Chemical & pharmaceutical bulletin
pub_type: 杂志文章
doi:10.1248/cpb.53.1451
更新日期:2005-11-01 00:00:00
abstract::Diphenhydramine, a sedating antihistamine, is an agonist of human bitter taste receptor 14 (hTAS2R14). Diphenhydramine hydrochloride (DPH) was used as a model bitter medicine to evaluate whether the umami dipeptides (Glu-Glu and Asp-Asp) and their constituent amino acids (Glu, Asp) could suppress its bitterness intens...
journal_title:Chemical & pharmaceutical bulletin
pub_type: 杂志文章
doi:10.1248/cpb.c19-00736
更新日期:2020-01-01 00:00:00
abstract::Four vitamin D3 analogues (7a, 7b, 7c and 7d) bearing a hydroxyalkoxy group at the 2 beta-position were synthesized from the alpha-epoxide (5). The C-3 analogue (7b) showed the highest potency for elevating plasma calcium levels in rats. Furthermore, the 25-hydroxylated C-3 analogue (ED-71) (3), prepared from the 25-h...
journal_title:Chemical & pharmaceutical bulletin
pub_type: 杂志文章
doi:10.1248/cpb.41.1111
更新日期:1993-06-01 00:00:00
abstract::Two new lignans, pseuderesinol (1), pseuderanoside (2) and a new triterpene, pseuderanic acid (3) were isolated from the dried root of Pseuderanthemum carruthersii (SEEM.) GUILL. var. atropurpureum (BULL.) FOSB. (Acanthaceae), together with ten known compounds, including five lignans, (+)-eudesmin (4), (+)-magnolin (5...
journal_title:Chemical & pharmaceutical bulletin
pub_type: 杂志文章
doi:10.1248/cpb.c12-00222
更新日期:2012-01-01 00:00:00
abstract::Seven halogenated derivatives of delta 9-tetrahydrocannabinol (delta 9-THC, 1) substituted on the aromatic ring at the 2 and/or 4 position, 2 (4)-fluoro- (2), 2,4-difluoro- (3), 2-chloro- (4), 2-bromo- (5), 2,4-dibromo- (6), 2-iodo- (7) and 2,4-diiodo-delta 9-THC (8) were synthesized and pharmacological effects such a...
journal_title:Chemical & pharmaceutical bulletin
pub_type: 杂志文章
doi:10.1248/cpb.46.1462
更新日期:1998-09-01 00:00:00
abstract::The stereoselective introduction of an allyl group into the angular position of 2-(TBS-oxymethyl)-2,3,4,6,7,8-hexahydro-1-benzopyran-5-one was accomplished using Birch reduction and an enolate trapping reaction. It was determined that the allyl group was introduced via an unexpected conformation-flipped from the initi...
journal_title:Chemical & pharmaceutical bulletin
pub_type: 杂志文章
doi:10.1248/cpb.53.207
更新日期:2005-02-01 00:00:00
abstract::To find candidates with high antimicrobial and low hemolytic activities, many gramicidin S (GS) analogs of various ring sizes have been designed and synthesized. However, syntheses of antimicrobially active analogues of GS having a disordered symmetry structure from C(2) have almost never been reported, because the st...
journal_title:Chemical & pharmaceutical bulletin
pub_type: 杂志文章
doi:10.1248/cpb.59.1481
更新日期:2011-01-01 00:00:00
abstract::A simple method to synthesize (+/-)-2-O-(4-coumaroyl)-3-(4-hydroxyphenyl)lactic acid (1), a key intermediate in rosmarinic acid biosynthesis in higher plant cells, was established by condensation of protected 4-coumaric acid and (+/-)-3-(4-hydroxyphenyl)lactic acid followed by deprotection. A stable supply of 1 thus a...
journal_title:Chemical & pharmaceutical bulletin
pub_type: 杂志文章
doi:10.1248/cpb.49.1644
更新日期:2001-12-01 00:00:00
abstract::A novel C-methylated biflavone, taiwanhomoflavone-B (1), together with known compounds, 7,4',7"-tri-O-methylamentoflavone, 6-C-methylnaringenin and apigenin-7-O-beta-glucoside were isolated from an ethanolic extract of Cephalotaxus wilsoniana. The structure of 1 was elucidated on the basis of spectroscopic analysis. T...
journal_title:Chemical & pharmaceutical bulletin
pub_type: 杂志文章
doi:10.1248/cpb.50.1607
更新日期:2002-12-01 00:00:00
abstract::A series of novel benzo[4,5]canthin-6-ones, bearing the N'-(substituted benzylidene)-carbohydrazide (11a-e) and N-alkylcarboxamide (13a-g) moieties at position-2, were synthesized and screened for their in vitro antitumor activity, against seven human cancer cell lines, and for antitrypanosomal and antileishmanial act...
journal_title:Chemical & pharmaceutical bulletin
pub_type: 杂志文章
doi:10.1248/cpb.c12-00356
更新日期:2012-01-01 00:00:00
abstract::A prevention method of the sorption of bromhexine HCl to plastic materials used in packaging was investigated. Four kinds of plastic packaging materials were used: Polyethylene (PE), polyethylene terephthalate (PET), polypropylene (PP) and polyacrylonitrile (PAN). Three polyethylenes having different densities were us...
journal_title:Chemical & pharmaceutical bulletin
pub_type: 杂志文章
doi:10.1248/cpb.40.3110
更新日期:1992-11-01 00:00:00
abstract::Intramolecular [2+2] cycloaddition of γ,δ-unsaturated ketenes derived from hex-5-enoyl chloride derivatives gave bicyclo[2.1.1]hexan-5-ones with complete regioselectivity. ...
journal_title:Chemical & pharmaceutical bulletin
pub_type: 杂志文章
doi:10.1248/cpb.60.548
更新日期:2012-01-01 00:00:00
abstract::From the quaternary alkaloidal fraction of the dried tubers of Stephania cepharantha, two new isoquinoline alkaloids, stecepharine and tetradehydroreticuline have been isolated along with the known compounds, magnoflorine, menisperine, steponine, cyclanoline, oblongine, cis-N-methylcapaurine and 2'-N-methylisotetrandr...
journal_title:Chemical & pharmaceutical bulletin
pub_type: 杂志文章
doi:10.1248/cpb.48.370
更新日期:2000-03-01 00:00:00
abstract::Six new furostanol saponins called trigoneosides Ia, Ib, IIa, IIb, IIIa, and IIIb were isolated from a medicinal foodstuff, fenugreek seed, the seed of Trigonella foenum-graecum L. (Leguminosae) originating from India, together with two known saponins, glycoside D and trigofoenoside A. The structures of trigoneosides ...
journal_title:Chemical & pharmaceutical bulletin
pub_type: 杂志文章
doi:10.1248/cpb.45.81
更新日期:1997-01-01 00:00:00
abstract::A series of 43 stilbene derivatives that showed cytotoxicity against human lung carcinoma (A549) was analyzed using comparative molecular field analysis (CoMFA) for defining the hypothetic pharmacophore model. The polyoxylated stilbenes were found to be active inhibitors of tubulin polymerization. Several cis-stilbene...
journal_title:Chemical & pharmaceutical bulletin
pub_type: 杂志文章
doi:10.1248/cpb.51.516
更新日期:2003-05-01 00:00:00
abstract::Chemical investigation on the constituents of the cones of Cycas beddomei has resulted in the isolation of a new biflavonoid, 2,3-dihydro-4'''-O-methyl amentoflavone, along with 2,3,2'',3''-tetrahydro hinokiflavone, 2,3,2'',3''-tetrahydro amentoflavone, 2,3-dihydro amentoflavone. The last two compounds were not report...
journal_title:Chemical & pharmaceutical bulletin
pub_type: 杂志文章
doi:10.1248/cpb.53.135
更新日期:2005-01-01 00:00:00
abstract::Four new lignans, 3',4'-O,O-demethylenehinokinin (1), chamalignolide (2), 8'beta-hydroxyhinokinin (3) and 7beta,8beta-epoxyzuonin A (4), as well as (-)-hinokinin (5), and (-)-zuonin A (6), were isolated from the heartwood of Chamaecyparis obtusa var. formosana. The structures of these lignans were unambiguously determ...
journal_title:Chemical & pharmaceutical bulletin
pub_type: 杂志文章
doi:10.1248/cpb.50.978
更新日期:2002-07-01 00:00:00
abstract::6-Amino-6-deoxyfumagillol (5) was synthesized by reductive amination of 6-oxo-6-deoxyfumagillol (4), which was obtained by oxidation of fumagillol (2). The reduction proceeded stereoselectively by the equatorial attack of hydride and 5 was found to have the same stereochemistry as that of 2. Several derivatives of 5 w...
journal_title:Chemical & pharmaceutical bulletin
pub_type: 杂志文章
doi:10.1248/cpb.40.575
更新日期:1992-03-01 00:00:00
abstract::Fourteen flavonol glycosides including two new compounds were isolated from the leaves of two Diospyros plants (D. cathayensis and D. rhombifolia). The structures of isolated compounds were determined by spectroscopic analysis. The scavenging activity of 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical of the isolated com...
journal_title:Chemical & pharmaceutical bulletin
pub_type: 杂志文章
doi:10.1248/cpb.53.591
更新日期:2005-05-01 00:00:00
abstract::A novel method for thermodynamic stability studies of polymorphic drug substances has been developed. In order to estimate the transition temperature for an enantiotropic polymorphic pair, a formula for calculating the temperature at which the solubilities of each polymorph become equal has been derived with heat of s...
journal_title:Chemical & pharmaceutical bulletin
pub_type: 杂志文章
doi:10.1248/cpb.50.263
更新日期:2002-02-01 00:00:00
abstract::Analogues with the scaffolds of 3-cyano-4-alkoxyphenyl-6-bromoaryl-2-pyridone and 2-amino-3-cyano-4-alkoxyphenyl-6-bromoarylpyridine were synthesized. Cyclization of the 2-amino derivatives with formic acid and formamide gave the corresponding pyrido[2,3-d]pyrimidin-4(3H)-one and the pyrido[2,3-d]-pyrimidin-4-amine de...
journal_title:Chemical & pharmaceutical bulletin
pub_type: 杂志文章
doi:10.1248/cpb.c12-00993
更新日期:2013-01-01 00:00:00
abstract::A convenient synthesis of immunosuppressive agent FTY720 (1) using the Petasis reaction was developed. 4-Octylbenzaldehyde (9) was converted into 1-ethenyl-4-octylbenzene (11) by two-step synthesis. Hydroboration of 11 using catecholborane and hydrolysis gave (E)-2-(4-octylphenyl)vinylboronic acid (4). The Petasis rea...
journal_title:Chemical & pharmaceutical bulletin
pub_type: 杂志文章
doi:10.1248/cpb.53.100
更新日期:2005-01-01 00:00:00
abstract::Debenzylating enzyme from Aspergillus niger enzyme (commercial crude cellulase) catalyzes the hydrolysis of cetraxate benzyl ester hydrochloride (2), a precursor of the antiulcer agent (1). The enzyme was highly purified by three kinds of chromatographies (hydrophobic, ion exchange, gel filtration) with a recovery of ...
journal_title:Chemical & pharmaceutical bulletin
pub_type: 杂志文章
doi:10.1248/cpb.37.2929
更新日期:1989-11-01 00:00:00
abstract::A series of dibenzofurans were efficiently and conveniently synthesized via one-pot consecutive C(sp(2))-O bond formation reaction (SNAr) in the presence of anhydrous K(2)CO(3), followed by C(sp(2))-C(sp(2)) bond formation reaction (intramolecular palladium-catalyzed aryl-aryl coupling reaction) between aryl halides a...
journal_title:Chemical & pharmaceutical bulletin
pub_type: 杂志文章
doi:10.1248/cpb.56.1496
更新日期:2008-10-01 00:00:00
abstract::We investigated the kinetics of in vitro transformation of a dichlorinated propyl paraben (2-propyl 3,5-dichloro-4-hydroxybenzoate; Cl2PP) by the rat liver S9 fraction and assessed the aryl hydrocarbon receptor (AhR) agonist activity of the metabolite products identified in HPLC and GC/MS analysis and by metabolite sy...
journal_title:Chemical & pharmaceutical bulletin
pub_type: 杂志文章
doi:10.1248/cpb.c15-00977
更新日期:2016-01-01 00:00:00
abstract::A high-performance liquid chromatographic method and a UV derivative spectrophotometric method for the determination of famciclovir, a highly active antiviral agent, in tablets were developed in the present work. The various parameters, such as linearity, precision, accuracy, specificity, robustness, limit of detectio...
journal_title:Chemical & pharmaceutical bulletin
pub_type: 杂志文章
doi:10.1248/cpb.54.819
更新日期:2006-06-01 00:00:00
abstract::Invasive fungal disease constitutes a growing health problem and development of novel antifungal drugs with high potency and selectivity against new fungal molecular targets are urgently needed. In order to develop potent antifungal agents, a novel series of 6-alkyl-indolo[3,2-c]-2H-thiochroman derivatives were synthe...
journal_title:Chemical & pharmaceutical bulletin
pub_type: 杂志文章
doi:10.1248/cpb.c16-00366
更新日期:2016-09-01 00:00:00
abstract::Benzoxazinorifamycin reacted with various secondary amines to yield various 5'-substituted aminobenzoxazinorifamycin derivatives. The derivatives exhibited potent activities against gram-positive bacteria and mycobacteria. The antimicrobial activities of these compounds against Mycobacterium tuberculosis and Mycobacte...
journal_title:Chemical & pharmaceutical bulletin
pub_type: 杂志文章
doi:10.1248/cpb.40.2707
更新日期:1992-10-01 00:00:00
abstract::A series of 4-phenoxy-2-(1-piperazinyl)quinazolines was synthesized and examined for anticonvulsive and antihypoxic activities. Many of the compounds exhibited potent anticonvulsive activity comparable to that of carbamazepine or phenytoin. Among them, 4-phenoxy-2-(4-propyl-1-piperazinyl)quinazoline (5w) was selected ...
journal_title:Chemical & pharmaceutical bulletin
pub_type: 杂志文章
doi:10.1248/cpb.38.681
更新日期:1990-03-01 00:00:00
abstract::A new phenolic glycoside, 3,4,5-trimethoxyphenol-1-(6-xylopyranosyl)glucopyranoside, was isolated together with twenty known compounds identified as koaburaside, 3,4,5-trimethoxyphenol, 5,7-dihydroxychromone-7-neohesperidoside, naringin, neoeriocitrin, p-coumaric acid, vanillin, vanillic acid, coniferyl aldehyde, feru...
journal_title:Chemical & pharmaceutical bulletin
pub_type: 杂志文章
doi:10.1248/cpb.42.1669
更新日期:1994-08-01 00:00:00