Vladimir Zhabinskii - Academia.edu (original) (raw)
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Papers by Vladimir Zhabinskii
Brassinosteroids, 2003
One of characteristic physiological properties of new plant hormones brassinosteroids (BS), when ... more One of characteristic physiological properties of new plant hormones brassinosteroids (BS), when applied exogenously to vegetating plants, is their ability to stimulate plant growth and development. That is why their possible application in agriculture was considered still in the very beginning of BS investigations. Their progress has been extremely rapid. After discovery of brassinolide, the first member of the series, less than twenty years were necessary to start wide practical use of brassinosteroids in agriculture as crop-yieldincreasing and plant-protecting agents. In Russia and Belarus, the first BS-preparation, based on 24-epibrassinolide as active ingredient, has been officially registered in 1992 as potato crop-increasing agrochemical. Later a number of other crops and purposes for its agricultural use have been added. During the developing of practical adaptation of BS many problems connected with commercial-scale production and official status of new agricultural chemical have been solved. Among them: elaboration of economically reasonable synthetic methods for BS preparation, field-scale biological trials with different plant species, toxicological studies, etc. The accumulated experience and results of research programs of different laboratories opened up many new aspects of BS-activity that are very important for further development of this group of phytohormones to a new generation of agricultural chemicals, which are not-conflicting with the environment and explore a new principle in plant protection. These problems and perspectives of agricultural application of brassinosteroids are the subject of the article.
Organic & biomolecular chemistry, Jan 21, 2015
A novel approach for the preparation of steroids containing a chiral center at C-25 is reported. ... more A novel approach for the preparation of steroids containing a chiral center at C-25 is reported. The key stereochemistry inducing step was asymmetric alkylation of pseudoephenamine amides of steroidal C-26 acids. The reaction proceeded with high diastereoselectivity (dr > 99 : 1). The developed methodology was successfully applied to the synthesis of (25R)- and (25S)-cholestenoic acids as well as (25R)- and (25S)-26-hydroxy brassinolides.
Russian Journal of Bioorganic Chemistry - RUSS J BIOORG CHEM, 2002
The syntheses of (24S)-24,25-epoxycholesterol, (24S)-hydroxycholesterol, and 24-ketocholesterol a... more The syntheses of (24S)-24,25-epoxycholesterol, (24S)-hydroxycholesterol, and 24-ketocholesterol are described. The compounds belong to oxysterols, which can be considered to be the modulators of cholesterol metabolism. The asymmetric hydroxylation of desmosterol acetate according to Sharpless was used as the key reaction in the stereoselective introduction of functionality in position 24.
Journal of Labelled Compounds and Radiopharmaceuticals, 2011
Synthesis of labeled brassinosteroids (24-epibrassinolide and its biosynthetic precursors) contai... more Synthesis of labeled brassinosteroids (24-epibrassinolide and its biosynthetic precursors) containing three deuterium atoms in the terminal part of the side chain is reported. Labeling was achieved by three-step reductive transformation of carbethoxy group into methyl using lithium aluminium deuteride. The proposed method ensured high isotopic purity of (24R)-methyl brassinosteroids containing a label in a position which is not subjected to its loss.
Chemistry of Natural Compounds, 2012
[26-2H3]-Campesterin and [26-2H3]-campestanol were synthesized as standards for studying brassino... more [26-2H3]-Campesterin and [26-2H3]-campestanol were synthesized as standards for studying brassinolide biosynthesis.
Brassinosteroids, 2003
One of characteristic physiological properties of new plant hormones brassinosteroids (BS), when ... more One of characteristic physiological properties of new plant hormones brassinosteroids (BS), when applied exogenously to vegetating plants, is their ability to stimulate plant growth and development. That is why their possible application in agriculture was considered still in the very beginning of BS investigations. Their progress has been extremely rapid. After discovery of brassinolide, the first member of the series, less than twenty years were necessary to start wide practical use of brassinosteroids in agriculture as crop-yieldincreasing and plant-protecting agents. In Russia and Belarus, the first BS-preparation, based on 24-epibrassinolide as active ingredient, has been officially registered in 1992 as potato crop-increasing agrochemical. Later a number of other crops and purposes for its agricultural use have been added. During the developing of practical adaptation of BS many problems connected with commercial-scale production and official status of new agricultural chemical have been solved. Among them: elaboration of economically reasonable synthetic methods for BS preparation, field-scale biological trials with different plant species, toxicological studies, etc. The accumulated experience and results of research programs of different laboratories opened up many new aspects of BS-activity that are very important for further development of this group of phytohormones to a new generation of agricultural chemicals, which are not-conflicting with the environment and explore a new principle in plant protection. These problems and perspectives of agricultural application of brassinosteroids are the subject of the article.
Organic & biomolecular chemistry, Jan 21, 2015
A novel approach for the preparation of steroids containing a chiral center at C-25 is reported. ... more A novel approach for the preparation of steroids containing a chiral center at C-25 is reported. The key stereochemistry inducing step was asymmetric alkylation of pseudoephenamine amides of steroidal C-26 acids. The reaction proceeded with high diastereoselectivity (dr > 99 : 1). The developed methodology was successfully applied to the synthesis of (25R)- and (25S)-cholestenoic acids as well as (25R)- and (25S)-26-hydroxy brassinolides.
Russian Journal of Bioorganic Chemistry - RUSS J BIOORG CHEM, 2002
The syntheses of (24S)-24,25-epoxycholesterol, (24S)-hydroxycholesterol, and 24-ketocholesterol a... more The syntheses of (24S)-24,25-epoxycholesterol, (24S)-hydroxycholesterol, and 24-ketocholesterol are described. The compounds belong to oxysterols, which can be considered to be the modulators of cholesterol metabolism. The asymmetric hydroxylation of desmosterol acetate according to Sharpless was used as the key reaction in the stereoselective introduction of functionality in position 24.
Journal of Labelled Compounds and Radiopharmaceuticals, 2011
Synthesis of labeled brassinosteroids (24-epibrassinolide and its biosynthetic precursors) contai... more Synthesis of labeled brassinosteroids (24-epibrassinolide and its biosynthetic precursors) containing three deuterium atoms in the terminal part of the side chain is reported. Labeling was achieved by three-step reductive transformation of carbethoxy group into methyl using lithium aluminium deuteride. The proposed method ensured high isotopic purity of (24R)-methyl brassinosteroids containing a label in a position which is not subjected to its loss.
Chemistry of Natural Compounds, 2012
[26-2H3]-Campesterin and [26-2H3]-campestanol were synthesized as standards for studying brassino... more [26-2H3]-Campesterin and [26-2H3]-campestanol were synthesized as standards for studying brassinolide biosynthesis.