A new triterpenoid sapogenin from flowers of Bombax malabaricum / 中草药

Objective To study the chemical constituents from the flowers of Bombax malabaricum. Methods The compound was separated and purified by silica gel and gel column choromatography. The structure of the new compound was identified by NMR, HRMS (EIS), IR, UV, and single crystal X-ray diffraction. Results A new compound was isolated from the flowers of B. malabaricum and identified as 3β-acetoxy-22α,30-dihydroxyurs-20-ene. Conclusion Compound 1 was a ursane-type triterpenoid and named as mumian terpene A.

Bioactive A-ring rearranged limonoids from the root barks of

Screening active natural products, rapid identification, and accurate isolation are of great important for modern natural lead compounds discovery. We hereby reported the isolation of seven new neotecleanin-type limonoids (-), seven new limonoids with 5-oxatricyclo[5.4.0.11., 4.]hendecane ring system (-), and two new precursors (-) together with four known limonoids (-) from the root barks of . Their structures, including their absolute configurations, were elucidated based on analyses of HR-ESI-MS, 1D/2D NMR, ECD spectrum calculations and single-crystal X-ray diffraction techniques. Compounds , , , , , , showed significant anti-inflammatory activities in LPS-induced RAW 264.7 cell line, BV2 microglial cells, and -stimulated THP-1 human monocytic cells. Walrobsin M () exhibited anti-inflammatory activity with IC value of 7.96±0.36 μmol/L, and down-regulated phosphorylation levels of ERK and p38 in a dose-dependent manner.

Chemical constituents of Ajuga ovalifolia var. calantha / 中草药

Objective To investigate the chemical constituents of Ajuga ovalifolia var. calantha. Methods The 95% ethanol extract from the whole herb of A. ovalifolia var. calantha was separated and purified by column chromatography over silica gel, Sephadex LH-20, ODS, and RP-HPLC. Their chemical structures were identified on the basis of physicochemical characteristics and spectral analyses. Results Thirteen compounds were isolated and identified as (16S)-12,16-epoxy-11,14-dihydroxy-17 (15→16)-abeo-abieta- 8,11,13-trien-7-one (1), ajuforrestin B (2), ajudecumin A (3), 14,15-dihydroajugapitin (4), cyasterone (5), β-sitosterol (6), acacetin (7), apigenin (8), luteolin (9), scopoletin (10), isoscopoletin (11), 4-hydroxy-3-methoxy-benzaldehyde (12), and acetovanillon (13). Conclusion Compounds 1 and 10-13 are reported from the genus Ajuga Linn., and compounds 2-5 and 7 are isolated from this plant for the first time. Single crystal X-ray diffraction experiment is carried out for compound 1, and the crystal structure data of single crystal X-ray diffraction of compound 1 is obtained for the first time.

Determination methods for absolute configuration of natural products / 国际药学研究杂志

The physical, chemical, biological and pharmacological properties of natural products (NP)are closely related to their absolute configurations, and the determination of the NP configurations is a great challenge for natural product chemists and has attracted widespread attention of researchers. People have summed up a variety of determination methods, such as single-crystal X-ray diffraction (XRD), Mosher" s method based on the chemical reaction with the chiral reagents and nuclear magnetic resonance NMR, circular dichroism CD and organic synthesis methods, etc. These methods have advantages and disadvantages for the determination of absolute configuration of NP with different structure characteristics. This paper reviewes the principles, advantages and limitations of these common methods.

Synthesis and Crystal Structure of Two Nitro-Regioisomers of cis-4(4-Methoxyphenyl)-3-Methyl-2-Phenyl-1, 2, 3, 4-Tetrahydroquinoline / Síntesis y estudio de la estructura cristalina de dos nitro regioisómerosde la cis-4-(4-metoxifenil)-3-metil-2-fenil-1, 2, 3, 4-tetrahydroquinolina

Dos nitro-regioisómeros de la moléculacis-4-(4-metoxifenil)-3-metil-2-fenil-1,2,3,4-tetrahydroquinolina fueronpreparados vía una síntesis one-pot de tres componentes basada en lareacción de cicloadición imino Diels-Alder catalizada por BF3.OEt2. Sucompleta caracterización estructural se llevó a cabo usando la técnicade difracción de rayos-X de monocristal y métodos espectroscópicos.La pureza de los productos y la composición de las mezclas de reacciónfueron monitoreadas por cromatografía en capa fina (CCD). Losproductos fueron aislados y purificados usando cromatografía encolumna. Las sustancias fueron identificadas usando resonancia magnéticanuclear (RMN) y espectrometría de masas (EM). Los datos para lacaracterización por difracción de rayos-X fueron colectados usando undifractómetro Bruker AFC7S Mercury con radiación de Mo-Kα (λ =0.71073Å) a temperatura ambiente. Las estructuras de los regio-isómerosfueron confirmadas por 1H RMN y 13C RMN y la estructura cristalinafue estudiada usando la difracción de rayos-X de monocristal. El análisisespectroscópico (RMN, EM y difracción de rayos-X) mostró una completacaracterización y permitió establecer la correcta estereoquímica para elanillo tetrahidroquinolínico. El empaquetamiento molecular en el cristalpara el regioisómero 5-nitro 4 es producto de la combinación de enlaces dehidrógeno intermoleculares e interacciones de van der Waals, mientras queen el 7-nitro regioisómero 3 el empaquetamiento se debe principalmente ainteracciones intermoleculares débiles de tipo van der Waals y N—H••• π...

Here we synthesized two nitro regioisomersof cis-4-(4-methoxyphenyl)-3-methyl-2-phenyl-1,2,3,4-tetrahydroquinoline via the “one pot” three-componentimino Diels-Alder reaction catalyzed by BF3.OEt2and completed its structural characterization using thesingle crystal X-ray diffraction technique and otherspectroscopic methods. To monitor the purity of theproducts and the composition of the reaction mixtureswe used thin layer chromatography, and isolated andpurified the products by column chromatography. Thenusing nuclear magnetic resonance (NMR) and massspectrometry (MS) identified the substances. We collectedX-ray diffraction data for crystal characterization byusing a Bruker AFC7S Mercury diffractometer with Mo-Kα radiation (λ = 0.71073Å) at room temperature. Thestructures of these regioisomers were confirmed by 1HNMR and 13C NMR studies and studied their crystalstructure using single crystal X-ray diffraction technique.The spectroscopy analyses (NMR, GC-MS and X-raydiffraction) provided a complete characterizationand enabled the correct stereochemistry for thetetrahydroquinoline ring. We determined the molecularpacking for the 5-nitro regioisomer 4 is the product ofthe combination of intermolecular hydrogen bonds andvan der Waals interactions, while for 7-nitro regioisomer3 is mainly due to weak intermolecular van der Waalsinteractions and N—H··· π...

Dois nitro regioisómeros da molécula cis-4-(4-metoxifenil)-3-metil-2-fenil-1,2,3,4-tetrahydroquinolina foram preparados através de umasíntese de um só recipiente de três componentes com base na reacçãode imino Diels-Alder cicloadição catalisada BF3.OEt2 e sua completacaracterização estrutural foi realizada usando a técnica de difracçãocristalografia de raios X, e outros métodos espectroscópicos. A purezado produto e a composição das misturas reaccionais foram monitorizadaspor cromatografia em camada fina (CCD). Os produtos foram isoladose purificados utilizando cromatografia em coluna. As substâncias foramidentificadaos por ressonância magnética nuclear (RMN) e espectrometriade massa (EM). Os dados para caracterização por difração de raios Xforam coletados usando um Bruker AFC7S Mercury difratômetro comMo-Ka radiação (λ = 0,71073Å) à temperatura ambiente. As estruturasdosa regioisómeros foram confirmadaos por 1H RMN e 13C RMN aestrutura de cristal foi investigada usando difracção de raios X de cristalúnico. As análises espectroscópicas (RMN, EM e difracção de raios-X)demonstraram uma completa caracterização e permitiramu estabelecer aestereoquímica correcta de anel tetrahidroquinolínico. O empacotamentomolecular no cristal para 5-nitro regioisómero 4 é derivado de umacombinação de ligações de hidrogénio intermoleculares e interacções devan der Waals, e ao 7-nitro regioisómero 3 embalagens é principalmentedevido a interacções intermoleculares fracas do tipo van der Waals e N-H• • • π...