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Valentin A. Stonik Alla A. Kicha Timofey V. Malyarenko Natalia V. Ivanchina 《Marine drugs》2020,18(12)
Asterosaponins are a class of steroid oligoglycosides isolated from starfish with characteristic structures and diverse biological activities. In this review, we have attempted to combine the most important data concerning asterosaponins and give a list of these secondary metabolites with their structural peculiarities. The purpose of this review is to provide a brief but as complete as possible principal information about their chemical structures, taxonomic distribution in the marine environment, distribution in different geographical areas and depths, some properties, biological activities, and functions. Some other rare steroid metabolites from starfish, closely related in structures and probably biogenesis to asterosaponins, are also discussed. 相似文献
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王昕乔 《林业机械与木工设备》2013,(6)
阐述了刨花板行业发展现状,介绍了国内外环式刨片机的主要技术参数及环式刨片机行业标准修订的意义、方法、原则和主要内容. 相似文献
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对我校制订或修订的本科专业人才培养方案进行分析和总结,指出现有人才培养方案在执行过程中出现的问题,并提出修订我校人才培养方案的具体措施,从而进一步提高人才培养方案的科学性和实效性。 相似文献
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In this review, we discuss structural diversity, taxonomic distribution, biological activities, biogenesis, and synthesis of a rare group of terpenoids, the so-called malabaricane and isomalabaricane triterpenoids, as well as some compounds derived from them. Representatives of these groups were found in some higher and lower terrestrial plants, as well as in some fungi, and in a relatively small group of marine sponges. The skeletal systems of malabaricanes and isomalabaricanes are similar to each other, but differ principally in the stereochemistry of their tricyclic core fragments, consisting of two six-membered and one five-membered rings. Evolution of these triterpenoids provides variety of rearranged, oxidized, and glycoconjugated products. These natural compounds have attracted a lot of attention for their biosynthetic origin and biological activity, especially for their extremely high cytotoxicity against tumor cells as well as promising neuroprotective properties in nanomolar concentrations. 相似文献