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Zhang W.,Yanbian University | Han R.-B.,Yanbian University | Han R.-B.,Key Laboratory of Natural Resources of Changbai Mountain and Functional Molecules | Zhang W.-B.,Yanbian University | And 2 more authors.
Journal of Heterocyclic Chemistry

Eight new benzotriazoloazepine derivatives have been synthesized starting from 7-methoxy-2,3,4,5-tetrahydro-1H-2-benzo[c]azepin-1-one. The compounds 2a-c have been synthesized by the reaction of 7-methoxy-2,3,4,5-tetrahydro-1H-2- benzo[c]azepin-1-thione with various hydrazides. Reaction of 5 with hydrazine hydrate, followed by treatment of the resultant hydrazone with formic acid, gave corresponding 9-alkoxy-6,7-dihydro-5H-benzo[c][1,2,4]triazolo[4,3-a]azepine(6a, b). Cyclization of 5 with methyl carbazate gave 9-alkoxy-6,7-dihydro-2H-benzo[c] [1,2,4]triazolo[4,3-a]azepin-3(5H)-one (7a-c). The structures of the compounds were confirmed by their elemental analysis and spectral data. Their anticonvulsant activities have been initially screened. © 2013 HeteroCorporation. Source

Hu B.,Hong Kong Polytechnic University | Yao Z.-P.,Hong Kong Polytechnic University | Yao Z.-P.,Key Laboratory of Natural Resources of Changbai Mountain and Functional Molecules
Analytical Chemistry

Proteins are important substances in living organisms and characterization of proteins is an indispensible part for protein study. Analysis of proteins using electrospray ionization-mass spectrometry (ESI-MS) with porous substrates was investigated in this study. The results revealed that the ionization process had two stages. At the first stage, mobility and resulting spectra of proteins were similar to those obtained with conventional capillary-based ESI-MS. At the second stage, hydrophobic-hydrophobic interactions between proteins and the tip surfaces played an important role in mobility and detectability of protein ions, which were size and shape dependent, and a linear relationship could be found between the peak area of selected ion chromatogram and the cross section of protein ions. Preparative separation of proteins could be achieved by collecting the proteins remained on the porous substrates. These results led us to propose that electrospray ionization from porous substrates offer a potential approach for analysis of proteins and investigation of protein structures and conformations. © 2016 American Chemical Society. Source

Jin D.-C.,Yanbian University | Zhang W.-B.,Yanbian University | Piao F.-Y.,Yanbian University | Han R.-B.,Key Laboratory of Natural Resources of Changbai Mountain and Functional Molecules
Acta Crystallographica Section E: Structure Reports Online

In the title mol-ecule, C 18H 16ClN 3O 2, the seven-membered ring adopts an envelope conformation with the flap atom deviating by 0.801 (5) Å from the mean plane formed by the remaining non-H atoms. Inter-molecular N - H⋯O hydrogen bonds link the mol-ecules into centrosymmetric dimers. The crystal packing also exhibits weak inter-molecular C - H⋯N hydrogen bonds and π-π inter-actions with a short distance of 3.734 (3) Å between the centroids of the aromatic rings of neighbouring mol-ecules. © Jin et al. 2011. Source

Qu B.,Yanbian University | Li W.,Yanbian University | Chen Y.,Yanbian University | Chen Y.,Key Laboratory of Natural Resources of Changbai Mountain and Functional Molecules | Liu J.,Yanbian University
International Journal of Sustainable Development and World Ecology

Under Chinese culture it is believed that herbal medicine is always safe and wild food is always healthy. Generally, the rarer a plant, the higher its value. The booming economy in China has promoted tourism development in wilderness areas and wild medicinal and food plants are part of the attraction to tourists. Conflicts between wild plant exploitation and protection have emerged in many parts of China, such as Changbai Mountain. Changbai Mountain supports numerous medicinal and food plants but many have become rare and endangered. This paper numerically evaluates 30 plant species that have relatively high conservation value for each type (medicinal, ornamental and food), and briefly describes the uses of four to five top ranked species per type that need more protection on Changbai Mountain. This paper also addresses some tree species with important timber values on Changbai Mountain. Over 90% of China's medicinal, ornamental and food plant species, as well as valuable timber trees are found in the conifer-broadleaf mixed forest zone across the boundary of Changbai Mountain Nature Reserve. It is a major challenge to protect the native biodiversity of mixed forest on Changbai Mountain and more efforts need to be made to protect rare and endangered plant species with high economic value. © 2011 Taylor & Francis. Source

Zhu W.H.,Key Laboratory of Natural Resources of Changbai Mountain and Functional Molecules | Zhu W.H.,Yanbian University | Cao G.L.,Yanbian University | Li Y.,Yanbian Environmental Protection Agency | And 3 more authors.
Shengtai Xuebao/ Acta Ecologica Sinica

Rivers Play a Key role in Ecosystems and Society, and THEY Provide a range of Ecosystem Functions SUCH as Shelter and Food Source for an array of Biological species, aid in flood Management and Ecological Refuge Development Socially, rivers Accommodate Communities by PROVIDING a medium for transport, recreation, tourism, worship, ecosystem services and a place to experience the serenity of nature Tumen River is an international river which located in the national boundaries of China, North Korea and Russia. With the three countries have different management and policies, it has been being seriously destroyed by various human activities including contaminant discharge, damming, solidifying riverside, destroying vegetation in the riparian zone and etc., resulting in deterioration of water environment, degradation of biological communities and riverbed atrophying It brings bad affection on the social and economic development of Tumen River Basin area which also affects and restricts the regional economic development. Therefore, the restoration and maintenance of "healthy" river ecosystems have become important objective of river management. In this paper, we summarize the current health conditions of national and international river ecosystem, and establish an evaluation system for ecological health, which is suitable for the river ecosystem in Tumen River Basin. The system includes an objective layer, a rule layer with 5 factors and an index layer with 22 defined indexes. The objective layer generalized to the river health highly, reflecting the total level of the healthy condition of river by the river health index (RHI).The rule layers, which consider the river hydrology, river morphology, riparian zone, water quality parameters, aquatic organisms, reflected the river health attribute and level from different sides. The index layer included 22 qualitative and quantitative evaluation indicators. In this system, a health assessment index for river ecosystem is constructed based on five health stage criteria: primary health (81 Source

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