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Article: Birch bark research and development.

Krasutsky, Pavel A

2006 Volume 23, Issue 6, Page(s) 919–942

Abstract: This review will detail progress made in the previous decade on the chemistry and bioactivity of birch bark extractive products. Current and future applications of birch bark natural products in pharmaceuticals, cosmetics, and dietary supplements for the ...

Abstract	This review will detail progress made in the previous decade on the chemistry and bioactivity of birch bark extractive products. Current and future applications of birch bark natural products in pharmaceuticals, cosmetics, and dietary supplements for the prevention and treatment of cancer, HIV,and other human pathogens are reviewed. Current developments in the technology of birch bark processing are discussed. New approaches for the synthesis of potentially valuable birch bark triterpenoid derivatives are also reviewed.
MeSH term(s)	Betula/chemistry ; Biological Products/chemical synthesis ; Biological Products/chemistry ; Biological Products/isolation & purification ; Biological Products/pharmacology ; Molecular Structure ; Plant Bark/chemistry ; Plants, Medicinal/chemistry ; Triterpenes/chemical synthesis ; Triterpenes/chemistry ; Triterpenes/pharmacology
Chemical Substances	Biological Products ; Triterpenes
Language	English
Publishing date	2006-12
Publishing country	England
Document type	Journal Article ; Research Support, Non-U.S. Gov't ; Review
ZDB-ID	2002546-4
ISSN	1460-4752 ; 0265-0568
ISSN (online)	1460-4752
ISSN	0265-0568
DOI	10.1039/b606816b
Database	MEDical Literature Analysis and Retrieval System OnLINE

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Article ; Online: Electrophilic monoiodination of terminal alkenes.

Yemets, Sergiy V / Shubina, Tatyana E / Krasutsky, Pavel A

Organic & biomolecular chemistry

2013 Volume 11, Issue 17, Page(s) 2891–2897

Abstract: An excess of elemental iodine in N,N-dimethylacetamide enables effective 3/iodanylium-de-hydronation of terminal alkenes with 3-iodopropene derivatives and hydrogen iodide formation within minutes at room temperature. The optimal molar ratio of iodine to ...

Abstract	An excess of elemental iodine in N,N-dimethylacetamide enables effective 3/iodanylium-de-hydronation of terminal alkenes with 3-iodopropene derivatives and hydrogen iodide formation within minutes at room temperature. The optimal molar ratio of iodine to substrate was decreased to 1 : 1 when hydrogen iodide formed was oxidized on a platinum anode. The electrolytic oxidation recovers iodine as a reagent and diminishes the hydrogen iodide inhibitory action to accomplish the monoiodination. The proposed reaction mechanism is based on kinetic measurements and quantum mechanics calculations.
MeSH term(s)	Alkenes/chemical synthesis ; Alkenes/chemistry ; Kinetics ; Models, Molecular ; Molecular Conformation ; Oxidation-Reduction ; Quantum Theory
Chemical Substances	Alkenes
Language	English
Publishing date	2013-05-07
Publishing country	England
Document type	Journal Article ; Research Support, Non-U.S. Gov't
ZDB-ID	2097583-1
ISSN	1477-0539 ; 1477-0520
ISSN (online)	1477-0539
ISSN	1477-0520
DOI	10.1039/c3ob27348b
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Article ; Online: Toxicity of lupane derivatives on anionic membrane models, isolated rat mitochondria and selected human cell lines: Role of terminal alkyl chains.

Carvalho, Filipa S / Morais, Catarina M / Holy, Jon / Krasutsky, Dmytro / Yemets, Sergiy V / Krasutsky, Pavel A / Jurado, Amália S / Oliveira, Paulo J / Serafim, Teresa L

Chemico-biological interactions

2018 Volume 296, Page(s) 198–210

Abstract: Triterpenoids have multiple biological properties, although little information is available regarding their toxicity. The present study evaluates the toxicity of two new synthetic lupane derivatives using distinct biological models including synthetic ... ...

Abstract	Triterpenoids have multiple biological properties, although little information is available regarding their toxicity. The present study evaluates the toxicity of two new synthetic lupane derivatives using distinct biological models including synthetic lipids membranes, isolated liver and heart mitochondria fractions, and cell lines in culture. The two novel triterpenoids caused perturbations in the organization of synthetic lipid bilayers, leading to changes in membrane fluidity. Inhibition of cell proliferation and mitochondrial and nuclear morphological alterations were also identified. Inhibition of mitochondrial oxygen consumption, transmembrane electric potential depolarization and induction of the mitochondrial permeability transition pore was observed, although effects on isolated mitochondrial fractions were tissue-dependent (e.g. liver vs. heart). The size and length of hydrocarbon chains in the two molecules appear to be determinant for the degree of interaction with mitochondria, especially in the whole cell environment, where more barriers for diffusion exist. The results suggest that the positively charged triterpenoids target mitochondria and disrupt bioenergetics.
MeSH term(s)	Animals ; Anions/antagonists & inhibitors ; Cell Proliferation/drug effects ; Cells, Cultured ; Humans ; Lipid Bilayers/antagonists & inhibitors ; Lipid Bilayers/metabolism ; Male ; Mitochondria, Heart/chemistry ; Mitochondria, Heart/drug effects ; Mitochondria, Heart/metabolism ; Mitochondria, Liver/chemistry ; Mitochondria, Liver/drug effects ; Mitochondria, Liver/metabolism ; Mitochondrial Membrane Transport Proteins/drug effects ; Models, Biological ; Molecular Conformation ; Rats ; Rats, Wistar ; Triterpenes/chemistry ; Triterpenes/toxicity
Chemical Substances	Anions ; Lipid Bilayers ; Mitochondrial Membrane Transport Proteins ; Triterpenes ; mitochondrial permeability transition pore ; lupane (464-99-3)
Language	English
Publishing date	2018-10-04
Publishing country	Ireland
Document type	Journal Article
ZDB-ID	218799-1
ISSN	1872-7786 ; 0009-2797
ISSN (online)	1872-7786
ISSN	0009-2797
DOI	10.1016/j.cbi.2018.10.002
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Article: Birch bark research and development

Krasutsky, Pavel A.

Natural product reports. 2006 Nov. 22, v. 23, no. 6

2006

Abstract	This review will detail progress made in the previous decade on the chemistry and bioactivity of birch bark extractive products. Current and future applications of birch bark natural products in pharmaceuticals, cosmetics, and dietary supplements for the prevention and treatment of cancer, HIV, and other human pathogens are reviewed. Current developments in the technology of birch bark processing are discussed. New approaches for the synthesis of potentially valuable birch bark triterpenoid derivatives are also reviewed.
Keywords	Betula ; bark ; bioactive properties ; chemistry ; cosmetics ; drugs ; humans ; research and development ; triterpenoids
Language	English
Dates of publication	2006-1122
Size	p. 919-942.
Publishing place	The Royal Society of Chemistry
Document type	Article
ZDB-ID	2002546-4
ISSN	1460-4752 ; 0265-0568
ISSN (online)	1460-4752
ISSN	0265-0568
DOI	10.1039/b606816b
Database	NAL-Catalogue (AGRICOLA)

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Article ; Online: Dimethylaminopyridine derivatives of lupane triterpenoids are potent disruptors of mitochondrial structure and function.

Holy, Jon / Kolomitsyna, Oksana / Krasutsky, Dmytro / Oliveira, Paulo J / Perkins, Edward / Krasutsky, Pavel A

Bioorganic & medicinal chemistry

2010 Volume 18, Issue 16, Page(s) 6080–6088

Abstract: Development of mitochondrially-targeted drugs is receiving increasing attention because of the central roles these organelles play in energy production, reactive oxygen generation, and regulation of cell death pathways. Previous studies have demonstrated ...

Abstract	Development of mitochondrially-targeted drugs is receiving increasing attention because of the central roles these organelles play in energy production, reactive oxygen generation, and regulation of cell death pathways. Previous studies have demonstrated that both natural and synthetic triterpenoids can disrupt mitochondrial structure and function. In this study, we tested the ability of a number of dimethylaminopyridine (DMAP) derivatives of lupane triterpenoids to target mitochochondria in two human melanoma cell lines and an untransformed normal fibroblast line. These compounds induced a striking fragmentation and depolarization of the mitochondrial network, along with an inhibition of cell proliferation. A range of potencies among these compounds was noted, which was correlated with the number, position, and orientation of the DMAP groups. Overall, the extent of proliferation inhibition mirrored the effectiveness of mitochondrial disruption. Thus, DMAP derivatives of lupane triterpenoids can be potent mitochondrial perturbants that appear to suppress cell growth primarily via their mitochondrial effects.
MeSH term(s)	Aminopyridines/chemistry ; Aminopyridines/pharmacology ; Antineoplastic Agents/chemistry ; Antineoplastic Agents/pharmacology ; Cell Line ; Cell Line, Tumor ; Cell Proliferation/drug effects ; Humans ; Melanoma/drug therapy ; Mitochondria/drug effects ; Mitochondria/metabolism ; Mitochondria/ultrastructure ; Mitochondrial Membranes/drug effects ; Mitochondrial Membranes/metabolism ; Triterpenes/chemistry ; Triterpenes/pharmacology
Chemical Substances	Aminopyridines ; Antineoplastic Agents ; Triterpenes ; lupane (464-99-3)
Language	English
Publishing date	2010-08-15
Publishing country	England
Document type	Journal Article ; Research Support, Non-U.S. Gov't
ZDB-ID	1161284-8
ISSN	1464-3391 ; 0968-0896
ISSN (online)	1464-3391
ISSN	0968-0896
DOI	10.1016/j.bmc.2010.06.075
Database	MEDical Literature Analysis and Retrieval System OnLINE

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Zs.A 3815: Show issues

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Article: Double- and triple-consecutive O-insertion into tert-butyl and triarylmethyl structures.

Krasutsky, Pavel A / Kolomitsyn, Igor V / Krasutsky, Sergiy G / Kiprof, Paul

Organic letters

2004 Volume 6, Issue 15, Page(s) 2539–2542

Abstract: reaction: see text] The concecutive Criegee rearrangement reactions were studied for tert-butyl trifluoroacetate, triarylcarbinols, and benzophenone ketales with trifluoroperacetic acid (TFPAA) in trifluoroacetic acid (TFA). The formation of methyl ... ...

Abstract	[reaction: see text] The concecutive Criegee rearrangement reactions were studied for tert-butyl trifluoroacetate, triarylcarbinols, and benzophenone ketales with trifluoroperacetic acid (TFPAA) in trifluoroacetic acid (TFA). The formation of methyl acetate and methyl trifluoroacetate indicates that the consecutive double-O-insertion process has taken place for tert-butyl trifluoroacetate. The intermediate dimethoxymethylcarbonium ion was detected below 5 degrees C. A consecutive triple-O-insertion process has been observed for triarylmethanols and benzophenone ketals. A new high yield method of corresponding diaryl carbonates synthesis was developed.
Language	English
Publishing date	2004-07-22
Publishing country	United States
Document type	Journal Article
ISSN	1523-7060
ISSN	1523-7060
DOI	10.1021/ol049171p
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Article ; Online: New derivatives of lupane triterpenoids disturb breast cancer mitochondria and induce cell death.

Serafim, Teresa L / Carvalho, Filipa S / Bernardo, Telma C / Pereira, Gonçalo C / Perkins, Edward / Holy, Jon / Krasutsky, Dmytro A / Kolomitsyna, Oksana N / Krasutsky, Pavel A / Oliveira, Paulo J

Bioorganic & medicinal chemistry

2014 Volume 22, Issue 21, Page(s) 6270–6287

Abstract: Novel cationic dimethylaminopyridine derivatives of pentacyclic triterpenes were previously described to promote mitochondrial depolarization and cell death in breast and melanoma cell lines. The objective of this work was to further investigate in ... ...

Abstract	Novel cationic dimethylaminopyridine derivatives of pentacyclic triterpenes were previously described to promote mitochondrial depolarization and cell death in breast and melanoma cell lines. The objective of this work was to further investigate in detail the mechanism of mitochondrial perturbations, correlating those effects with breast cancer cell responses to those same agents. Initially, a panel of tumor and non-tumor cell lines was grown in high-glucose or glucose-free glutamine-containing media, the later forcing cells to synthesize ATP by oxidative phosphorylation only. Cell proliferation, cell cycle, cell death and mitochondrial membrane polarization were evaluated. Inhibition of cell proliferation was observed, accompanied by an arrest in the G1-cell cycle phase, and importantly, by loss of mitochondrial membrane potential. On a later time-point, caspase-9 and 3 activation were observed, resulting in cell death. For the majority of test compounds, we determined that cell toxicity was augmented in the galactose media. To investigate direct evidences on mitochondria isolated rat liver mitochondria were used. The results showed that the compounds were strong inducers of the permeability transition pore. Confirming our previous results, this work shows that the novel DMAP derivatives strongly interact with mitochondria, resulting in pro-apoptotic signaling and cell death.
MeSH term(s)	Animals ; Antineoplastic Agents/chemistry ; Antineoplastic Agents/pharmacology ; Apoptosis/drug effects ; Breast/drug effects ; Breast/pathology ; Breast Neoplasms/drug therapy ; Breast Neoplasms/pathology ; Cell Cycle/drug effects ; Cell Death/drug effects ; Cell Line, Tumor ; Cell Proliferation/drug effects ; Female ; Humans ; Male ; Membrane Potential, Mitochondrial/drug effects ; Mitochondria/drug effects ; Mitochondria/pathology ; Rats ; Rats, Wistar ; Triterpenes/chemistry ; Triterpenes/pharmacology
Chemical Substances	Antineoplastic Agents ; Triterpenes ; lupane (464-99-3)
Language	English
Publishing date	2014-11-01
Publishing country	England
Document type	Journal Article ; Research Support, Non-U.S. Gov't
ZDB-ID	1161284-8
ISSN	1464-3391 ; 0968-0896
ISSN (online)	1464-3391
ISSN	0968-0896
DOI	10.1016/j.bmc.2014.08.013
Database	MEDical Literature Analysis and Retrieval System OnLINE

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Zs.A 3815: Show issues

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Je nach Verfügbarkeit (siehe Angabe bei Bestand)
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Jg. 1995 - 2021: Lesesall (2.OG)
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Article: Paleolimnology of a freshwater estuary to inform Area of Concern nutrient delisting efforts

Alexson, ElizabethE / Euan D. Reavie / Richard P. Axler / Sergiy V. Yemets / Pavel A. Krasutsky / Mark B. Edlund / Robert W. Pillsbury / Diane Desotelle

Journal of paleolimnology. 2018 Mar., v. 59, no. 3

2018

Abstract: The St. Louis River Estuary (SLRE), a freshwater estuary bordering Duluth, Minnesota, Superior, Wisconsin, and the most western point of Lake Superior (46.74°, − 92.13°), has a long history of human development since Euro-American settlement ~ 200 years ... ...

Abstract	The St. Louis River Estuary (SLRE), a freshwater estuary bordering Duluth, Minnesota, Superior, Wisconsin, and the most western point of Lake Superior (46.74°, − 92.13°), has a long history of human development since Euro-American settlement ~ 200 years ago. Due to degradation from logging, hydrologic modification, industrial practices, and untreated sewage, the SLRE was designated an Area of Concern in 1987. Action has been taken to restore water quality including the installation of the Western Lake Superior Sanitary District in 1978 to help remove beneficial use impairments. A better understanding of historical impacts and remediation is necessary to help document progress and knowledge gaps related to water quality, so a paleolimnological study of the SLRE was initiated. Various paleolimnological indicators (pigments, diatom communities, and diatom-inferred phosphorus) were analyzed from six cores taken throughout the SLRE and another from western Lake Superior. Reductions in eutrophic diatom taxa such as Cyclotella meneghiniana and Stephanodiscus after 1970 in certain cores suggest an improvement in water quality over the last 40 years. However, in cores taken from estuarine bay environments, persistence of eutrophic taxa such as Cyclostephanos dubius and Stephanodiscus binderanus indicate ongoing nutrient problems. Sedimentary pigments also indicate cyanobacteria increases in bays over the last two decades. Diatom model-inferred phosphorus and contemporary monitoring data suggest some of the problems associated with excess nutrient loads have been remediated, but modern conditions (internal phosphorus loading, changing climate) may be contributing to ongoing water quality impairments in some locations. The integrated record of biological, chemical, and physical indicators preserved in the sediments will aid state and federal agencies in determining where to target their resources.
Keywords	Bacillariophyceae ; Cyanobacteria ; Cyclotella meneghiniana ; Stephanodiscus ; climate change ; estuaries ; eutrophication ; freshwater ; human development ; limnology ; logging ; monitoring ; paleontology ; phosphorus ; pigments ; pollution load ; remediation ; rivers ; sediments ; sewage ; water quality ; Lake Superior ; Minnesota ; Wisconsin
Language	English
Dates of publication	2018-03
Size	p. 373-395.
Publishing place	Springer Netherlands
Document type	Article
ZDB-ID	1478181-5
ISSN	1573-0417 ; 0921-2728
ISSN (online)	1573-0417
ISSN	0921-2728
DOI	10.1007/s10933-017-0014-8
Database	NAL-Catalogue (AGRICOLA)

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Article ; Online: Trifuoroperacetic acid in consecutive Criegee rearrangement and carboxonium ions generation

Pavel A. Krasutsky / Igor V. Kolomitsyn

ARKIVOC, Vol 2005, Iss 4, Pp 151-

2005 Volume 171

Keywords	Organic chemistry ; QD241-441
Language	English
Publishing date	2005-05-01T00:00:00Z
Publisher	Arkat USA, Inc.
Document type	Article ; Online
Database	BASE - Bielefeld Academic Search Engine (life sciences selection)

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Article: Stereoselectivity of A-ring contraction for 3-oxotriterpenoids

Kacharov, Alexey D / Fokin, Andrey A / Kacharova, Liliya M / Krasutsky, Pavel A / Nemykin, Victor N / Yemets, Sergiy V

RSC advances. 2013 Sept. 30, v. 3, no. 41

2013

Abstract: The A-ring oxidation/contraction of 3-oxotriterpenoids was developed as a two-step and “one pot” process. A benzylic acid type rearrangement of triterpenoid diosphenols gives (S)- as major and (R)-α-hydroxycarboxylic acids as minor reaction products. The ...

Abstract	The A-ring oxidation/contraction of 3-oxotriterpenoids was developed as a two-step and “one pot” process. A benzylic acid type rearrangement of triterpenoid diosphenols gives (S)- as major and (R)-α-hydroxycarboxylic acids as minor reaction products. The absolute configurations were determined from the X-ray crystal structure analysis. The mechanism of ring contraction was modelled computationally at the DFT and MP2 levels of theory. The tautomeric triterpenoid A-seco δ-oxocarboxylic acids and A-ring hydroxy lactones formed after deep oxidation/acidification of 3-oxotriterpenoids.
Keywords	acidification ; carboxylic acids ; crystal structure ; lactones ; oxidation ; stereoselectivity ; triterpenoids
Language	English
Dates of publication	2013-0930
Size	p. 19057-19063.
Publishing place	The Royal Society of Chemistry
Document type	Article
ISSN	2046-2069
DOI	10.1039/c3ra42929f
Database	NAL-Catalogue (AGRICOLA)

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