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1.
Molecules ; 26(7)2021 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-33915860

RESUMO

Polymorphism exhibits different physicochemical properties, which can impact the bioavailability and bioactivity of solid drugs. This study focused on identifying the polymorphs of ginsenoside compound K (CK) and studying their different behaviors in pharmacokinetics (PK) and pharmacodynamics (PD). Four CK polymorphs (form I, II, III, and IV) from organic solvents were characterized by scanning electron microscope (SEM), differential scanning calorimetry (DSC), thermogravimetric analysis (TGA), Fourier transform infrared spectroscopy (FTIR), and powder X-ray diffraction (PXRD). A feasible LC-MS/MS method was exploited to determine the PK parameters. Form II displayed the most exposure, followed by form I, III, and IV. Notably, all forms showed sex dimorphism, and the bioavailability in the female group was about two-fold higher than in the male group. The PD properties were investigated in carrageenan-induced acute paw inflammation, and form II at 20 mg/kg showed significant inhibition of edema by 42.7%. This study clarified the polymorphic, PK, and PD characters of four crystal forms of CK, and the data suggested that form II had the best efficacy for drug development.


Assuntos
Anti-Inflamatórios/química , Anti-Inflamatórios/farmacocinética , Ginsenosídeos/química , Ginsenosídeos/farmacocinética , Animais , Área Sob a Curva , Fenômenos Químicos , Estrutura Molecular , Ratos , Análise Espectral , Relação Estrutura-Atividade
2.
Molecules ; 12(11): 2507-14, 2007 Nov 13.
Artigo em Inglês | MEDLINE | ID: mdl-18065954

RESUMO

The synthesis of optically active [N-tosyl-(R)-prolyloxy]-2(S)-[4-cyano-8,8-ethylenedioxy-5-oxo-5,6,7,8-tetrahydroindolizin-3-yl] acetate (4a), a key intermediate for the total asymmetric synthesis of 20(S)-camptothecin anticancer drugs, is described. Its structure was characterized by 2D-NMR techniques and the absolute configuration was further confirmed for the first time by X-ray crystal structure analysis.


Assuntos
Acetatos , Camptotecina , Acetatos/síntese química , Acetatos/química , Camptotecina/síntese química , Camptotecina/química , Cristalografia por Raios X , Conformação Molecular , Estrutura Molecular , Relação Estrutura-Atividade
3.
Nat Prod Res ; 22(18): 1605-9, 2008 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-19085415

RESUMO

A new norsesquiterpene nephthediol (1) and a new sesquiterpene nephthetetraol (2) were isolated with guaianediol (3) from a soft coral of the genus Nephthea. Their structures were deduced on the basis of spectroscopic methods.


Assuntos
Antozoários/química , Sesquiterpenos/isolamento & purificação , Animais , Estrutura Molecular , Ressonância Magnética Nuclear Biomolecular , Sesquiterpenos/química
4.
J Asian Nat Prod Res ; 7(2): 107-13, 2005 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-15621611

RESUMO

The new tetracyclic diterpenoid confertdiate (1) and two new ceramides, (2) and (3), have been isolated from the soft coral Sinularia conferta, collected from Sanya Bay, Hainan Island, China. Their structures have been elucidated by spectroscopic analysis, and comparison of the 13C NMR data with those of the known diterpenoid isomandapamate confirmed the structure of 1.


Assuntos
Antozoários/química , Ceramidas/isolamento & purificação , Diterpenos/isolamento & purificação , Animais , Ceramidas/química , China , Cromatografia em Gel , Diterpenos/química , Estrutura Molecular , Ressonância Magnética Nuclear Biomolecular , Espectrometria de Massas por Ionização por Electrospray , Espectrofotometria Infravermelho
5.
Arch Pharm (Weinheim) ; 338(10): 457-61, 2005 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-16211654

RESUMO

2-(Arylcarbonylmethyl)thio-6alpha-naphthylmethyl derivatives of dihydro-alkoxy-benzyl-oxopyrimidines (DABO) were newly found to exhibit activity against both HIV-1 and HIV-2. To further explore their structure-activity relationship, the modified S-DABO analogues (5a-g and 6e-f) with a 1-naphthylthio or phenylthio group at the C-6 position were synthesized. S-Alkylation of 5-ethyl-2-thiouracil with substituted 2-bromo-acetophenones provided crude 2-[(arylcarbonylmethyl)thio]-5-ethyl-(3H)-uracil 2a-e, which was directly subjected to toluenesulfonylation with TsCl to afford disulfonate 4a-e. Substitution of 4a-e with arylthiol afforded the desired S-DABO analogues 5a-g and 6e-f. The compounds were evaluated for their in vitro anti-HIV activity in MT-4 cells. The IC(50) values for anti-HIV-1 activity fall into the range 0.37-29.50 microM, and the IC(50) values for anti-HIV-2 activity fall into the range 23.11-181.07 microM. The results indicated that these compounds are moderately active against HIV-1 and HIV-2.


Assuntos
Transcriptase Reversa do HIV/antagonistas & inibidores , HIV-1/efeitos dos fármacos , HIV-2/efeitos dos fármacos , Pirimidinonas/farmacologia , Inibidores da Transcriptase Reversa/farmacologia , Fármacos Anti-HIV/síntese química , Fármacos Anti-HIV/farmacologia , Linhagem Celular , Humanos , Concentração Inibidora 50 , Pirimidinonas/síntese química , Inibidores da Transcriptase Reversa/síntese química , Relação Estrutura-Atividade
6.
Chem Pharm Bull (Tokyo) ; 53(7): 743-6, 2005 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-15997127

RESUMO

An efficient and highly stereoselective total synthesis of d-biotin has been achieved starting from cis-1,3-dibenzyl-2-imidazolidone-4,5-dicarboxylic acid (2) with an overall yield of 33%. Polymer-supported oxazaborolidine-catalyzed asymmetric reduction of meso-cyclic imide 4 constitutes the key synthetic step in introducing stereogenic centers into the d-biotin molecule.


Assuntos
Biotina/síntese química , Lactonas/química , Compostos de Sulfidrila/química , Espectroscopia de Ressonância Magnética , Espectrometria de Massas por Ionização por Electrospray
7.
Acta Crystallogr C ; 60(Pt 7): o505-6, 2004 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-15237179

RESUMO

In the title compound, C10H14BrNO3, the six-membered lactone ring is in a boat conformation, with the two carbonyl groups cis to one another across the boat basal plane. C-H...O hydrogen bonds and weak C-H...Br interactions stabilize the crystal structure.

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