ABSTRACT
Four new cyclohexene derivatives cladoscyclitols A-D (1-4) and one new ribofuranose phenol derivative 4-O-α-D-ribofuranose-2-pentyl-3-phemethylol (5) were obtained from the EtOAC extract of the mangrove-derived endophytic fungus Cladosporium sp. JJM22. The structures were elucidated by extensive NMR and MS analysis, while the absolute configurations of the stereogenic carbons were established based on quantum-chemical electronic circular dichroism calculations or comparison of the optical rotations with those of related compounds. Compounds 2 and 5 displayed potent inhibitory activity against α-glucosidase with the IC50 values of 2.95 and 2.05 µM, respectively.
Subject(s)
Cladosporium/chemistry , Cyclohexenes/pharmacology , Glycoside Hydrolase Inhibitors/pharmacology , Rhizophoraceae/microbiology , China , Cyclohexenes/isolation & purification , Endophytes/chemistry , Glycoside Hydrolase Inhibitors/isolation & purification , Microbial Sensitivity Tests , Molecular StructureABSTRACT
A tertiary component with higher molecular weight of epoxy terminated polysiloxane (DMS-E11) was incorporated into the diglycidyl ether of bisphenol-A (DGEBA)/thermoplastic polyetherimide (PEI) blends. In this ternary DGEBA/PEI/DMS-E11 system, 25 or 30 wt% PEI and no more than 20 wt% DMS-E11 were used to ensure the formation of a continuous PEI-rich phase via reaction induced phase separation for optimum mechanical properties of blends. The results of morphology monitoring by OM and TRLS indicated that the addition of DMS-E11 could accelerate phase separation of DGEBA/PEI. Obvious differences were observed by SEM/EDS in the final morphologies of the blends. DMS-E11 localized in the PEI-rich phase continuously while it separated with DGEBA into spherical particles in the DGEBA-rich phase. DMA measurements found that the storage modulus and T g decreased with DMS-E11 content but were compensated partly by the presence of PEI. The results of tensile tests confirmed the synergistic strengthening for epoxy resin from PEI and DMS-E11.
ABSTRACT
Two new compounds (1 and 2), together with six known compounds (3-8), were obtained from the Cladosporium sp. JJM22, an endophytic fungus isolated from the stem bark of the mangrove plant Ceriops tagal collected in South China Sea. Their structures were elucidated on the basis of detailed spectroscopic analysis. The absolute configurations of 1 and 2 were confirmed by the comparison of optical rotation and the CD data with those of known compounds. The inhibitory activities of the isolated compounds against six terrestrial pathogenic bacteria and human cervical carcinoma Hela cell line were evaluated. Compound 3 exhibited a broad spectrum of antibacterial activities.
Subject(s)
Anti-Bacterial Agents/isolation & purification , Cladosporium/chemistry , Fungi/chemistry , Rhizophoraceae/microbiology , Anti-Bacterial Agents/pharmacology , Bacteria/drug effects , China , HeLa Cells/drug effects , Humans , Molecular Structure , Spectrum AnalysisABSTRACT
A new phenolic glycoside dendroside (1), together with seven known compounds (2-8) were isolated from the stems of Dendrobium nobile. The structures of these compounds were elucidated using comprehensive spectroscopic methods. The inhibitory activities of all compounds against three cancer cell lines HeLa, MCF-7 and A549 were evaluated.
Subject(s)
Dendrobium/chemistry , Glycosides/isolation & purification , Antineoplastic Agents, Phytogenic/pharmacology , Cell Line, Tumor , Glycosides/chemistry , Glycosides/pharmacology , Humans , Phenols/analysis , Plant Stems/chemistryABSTRACT
Five new lactone derivatives decumbic acids A and B (1 and 2), (-)-decumbic acid (3a), (-)- and (+)-dendrolactone (4a and 4b) together with four known compounds (3b and 5-7) were isolated from the stems of Dendrobium nobile. Their structures were elucidated using comprehensive spectroscopic methods. Compounds 3a and 3b, 4a and 4b were isolated as two pair of enantiomers by chiral HPLC. The absolute configurations of 1, 2, 3a, 4a and 4b were determined by optical rotation and X-ray crystallographic analysis. The inhibitory activities of all compounds against nine phytopathogenic fungi and three cancer cell lines were evaluated.
Subject(s)
Dendrobium/chemistry , Lactones/chemistry , Plant Stems/chemistry , Antifungal Agents/chemistry , Antifungal Agents/isolation & purification , Antineoplastic Agents, Phytogenic/chemistry , Antineoplastic Agents, Phytogenic/isolation & purification , Cell Line, Tumor , Fungi/drug effects , Humans , Lactones/isolation & purification , Molecular StructureABSTRACT
Based on linguistic term sets and hesitant fuzzy sets, the concept of hesitant fuzzy linguistic sets was introduced. The focus of this paper is the multicriteria decision-making (MCDM) problems in which the criteria are in different priority levels and the criteria values take the form of hesitant fuzzy linguistic numbers (HFLNs). A new approach to solving these problems is proposed, which is based on the generalized prioritized aggregation operator of HFLNs. Firstly, the new operations and comparison method for HFLNs are provided and some linguistic scale functions are applied. Subsequently, two prioritized aggregation operators and a generalized prioritized aggregation operator of HFLNs are developed and applied to MCDM problems. Finally, an illustrative example is given to illustrate the effectiveness and feasibility of the proposed method, which are then compared to the existing approach.
