Natural Reagents Research Articles

Total Enantioselective Synthesis and in vivo Biological Evaluation of a Novel Fluorescent BODIPY α‐Galactosylceramide.

ChemInformVolume 34, Issue 14 Natural Products Total Enantioselective Synthesis and in vivo Biological Evaluation of a Novel Fluorescent BODIPY α-Galactosylceramide. Yen Vo-Hoang, Yen Vo-Hoang Lab. Chim. Ther., CNRS, Fac. Sci. Pharm. Biol., Univ. R. Descartes, F-75270 Paris, Fr.Search for more papers by this authorLaurent Micouin, Laurent Micouin Lab. Chim. Ther., CNRS, Fac. Sci. Pharm. Biol., Univ. R. Descartes, F-75270 Paris, Fr.Search for more papers by this authorCatherine Ronet, Catherine Ronet Lab. Chim. Ther., CNRS, Fac. Sci. Pharm. Biol., Univ. R. Descartes, F-75270 Paris, Fr.Search for more papers by this authorGabriel Gachelin, Gabriel Gachelin Lab. Chim. Ther., CNRS, Fac. Sci. Pharm. Biol., Univ. R. Descartes, F-75270 Paris, Fr.Search for more papers by this authorMartine Bonin, Martine Bonin Lab. Chim. Ther., CNRS, Fac. Sci. Pharm. Biol., Univ. R. Descartes, F-75270 Paris, Fr.Search for more papers by this author Yen Vo-Hoang, Yen Vo-Hoang Lab. Chim. Ther., CNRS, Fac. Sci. Pharm. Biol., Univ. R. Descartes, F-75270 Paris, Fr.Search for more papers by this authorLaurent Micouin, Laurent Micouin Lab. Chim. Ther., CNRS, Fac. Sci. Pharm. Biol., Univ. R. Descartes, F-75270 Paris, Fr.Search for more papers by this authorCatherine Ronet, Catherine Ronet Lab. Chim. Ther., CNRS, Fac. Sci. Pharm. Biol., Univ. R. Descartes, F-75270 Paris, Fr.Search for more papers by this authorGabriel Gachelin, Gabriel Gachelin Lab. Chim. Ther., CNRS, Fac. Sci. Pharm. Biol., Univ. R. Descartes, F-75270 Paris, Fr.Search for more papers by this authorMartine Bonin, Martine Bonin Lab. Chim. Ther., CNRS, Fac. Sci. Pharm. Biol., Univ. R. Descartes, F-75270 Paris, Fr.Search for more papers by this author First published: 20 March 2003 https://doi.org/10.1002/chin.200314228Read the full textAboutPDF ToolsRequest permissionExport citationAdd to favoritesTrack citation ShareShare Give accessShare full text accessShare full-text accessPlease review our Terms and Conditions of Use and check box below to share full-text version of article.I have read and accept the Wiley Online Library Terms and Conditions of UseShareable LinkUse the link below to share a full-text version of this article with your friends and colleagues. Learn more.Copy URL Share a linkShare onFacebookTwitterLinked InRedditWechat No abstract is available for this article. Volume34, Issue14April 8, 2003 RelatedInformation

Total enantioselective synthesis and in vivo biological evaluation of a novel fluorescent BODIPY alpha-galactosylceramide.

Natural killer T (NKT) cells are a distinct subset of mature lymphocytes endowed with features of activated and regulatory T cells. alpha-Galactosylceramides (alpha-GalCers), the synthetic prototype of which is KRN7000, are the only natural reagents recognised by the T-cell receptor of NKT cells. The alpha-GalCer-activated NKT cells promptly release IFN gamma and IL-4 (IFN=interferon; IL=interleukin) and undergo apoptotic death within hours. In mice, activated NKT cells are responsible for antitumour activity and protection against autoimmune diseases. KRN7000 can thus be considered as the root of a family of novel immunoregulatory drugs. To get insights into the in vivo behaviour of alpha-galactosylceramides, an original fluorescent derivative has been prepared by following a convergent synthetic scheme. This strategy allows the introduction of different acyl chains, carbohydrate residues and various labels in the final steps of the synthesis. The fluorescent BODIPY probe derived from a versatile glycolipid precursor is as active as KRN7000 for inducing apoptosis of liver NKT cells. Fluorescence was detected in peritoneal macrophages and splenic antigen-presenting cells, in Kupffer-like cells in the liver, but not in lymphocytes.

Inhibitor specificity of recombinant and endogenous caspase-9.

Apoptosis triggered through the intrinsic pathway by radiation and anti-neoplastic drugs is initiated by the activation of caspase-9. To elucidate control mechanisms in this pathway we used a range of synthetic and natural reagents. The inhibitory potency of acetyl-Asp-Glu-Val-Asp-aldehyde ('Ac-DEVD-CHO'), benzyloxycarbonyl-Val-Ala-Asp-fluoromethylketone ('Z-VAD-FMK') and the endogenous caspase inhibitor X-chromosome-linked inhibitor of apoptosis protein ('XIAP') against recombinant caspase-9 were predictive of the efficacy of these compounds in a cell-free system. However, the viral proteins CrmA and p35, although potent inhibitors of recombinant caspase-9, had almost no ability to block caspase-9 in this system. These findings were also mirrored in cell expression studies. We hypothesize that the viral inhibitors CrmA and p35 are excluded from reacting productively with the natural form of active caspase-9 in vivo, making the potency of inhibitors highly context-dependent. This is supported by survival data from a mouse model of apoptosis driven by Sindbis virus expressing either p35 or a catalytic mutant of caspase-9. These results consolidate previous findings that CrmA is a potent inhibitor of caspase-9 in vitro, yet fails to block caspase-9-mediated cell death.

Effect of high concentrations of sucrose on the enzymatic activity of alpha-chymotrypsin.

The effect of the low-molecular-mass natural reagents in high concentrations is important for investigating enzymatic reactions in near "in vivo" conditions and for optimisation of biotechnology processes. A model system, including p-nitrophenyl acetate as substrate and alpha-chymotrypsin as proteolytic enzyme, has been used to study the effect of high concentrations of sucrose, both influencing the viscosity of the reaction medium and acting as a nucleophilic effector (activator) on the enzymatic reaction. A kinetic scheme at high concentrations of nucleophilic effectors (sucrose) has been proposed.

The neurofibromatosis 2 (NF2) tumor suppressor gene encodes multiple alternatively spliced transcripts.

Neurofibromatosis type 2 (NF2) is an autosomal dominantly-inherited disorder predisposing affected individuals to tumors of multiple cell types in the central nervous system, including meningiomas. A candidate tumor suppressor gene for this disorder has recently been cloned; the protein product of this gene has a predicted role in linking integral membrane proteins with the cytoskeleton. Utilizing reverse transcription-polymerase chain reaction (RT-PCR) analyses, we have identified a number of alternatively spliced transcription products encoded by the NF2 gene. These alternative splice variants were detected in RNA isolated from several sources, including primary leptomeningeal tissue and an established line of leptomeningeal cells (LMC). Several of these variants delete previously identified coding regions of this gene. Moreover, two of these splice variants add previously unrecognized exons to the NF2 coding region. These identified splice forms will serve as natural reagents for the functional dissection of the NF2 protein product(s). They also should be considered in studies investigating mutations of this gene in members of NF2 families and in tumor analyses.

ChemInform Abstract: HINDERED DIALKYLAMINO NUCLEOSIDE PHOSPHITE REAGENTS IN THE SYNTHESIS OF TWO DNA 51‐MERS

Chemischer InformationsdienstVolume 14, Issue 21 Natural Products ChemInform Abstract: HINDERED DIALKYLAMINO NUCLEOSIDE PHOSPHITE REAGENTS IN THE SYNTHESIS OF TWO DNA 51-MERS S. P. ADAMS, S. P. ADAMSSearch for more papers by this authorK. S. KAVKA, K. S. KAVKASearch for more papers by this authorE. J. WYKES, E. J. WYKESSearch for more papers by this authorS. B. HOLDER, S. B. HOLDERSearch for more papers by this authorG. R. GALLUPPI, G. R. GALLUPPISearch for more papers by this author S. P. ADAMS, S. P. ADAMSSearch for more papers by this authorK. S. KAVKA, K. S. KAVKASearch for more papers by this authorE. J. WYKES, E. J. WYKESSearch for more papers by this authorS. B. HOLDER, S. B. HOLDERSearch for more papers by this authorG. R. GALLUPPI, G. R. GALLUPPISearch for more papers by this author First published: May 24, 1983 https://doi.org/10.1002/chin.198321328Read the full textAboutPDF ToolsRequest permissionExport citationAdd to favoritesTrack citation ShareShare Give accessShare full text accessShare full-text accessPlease review our Terms and Conditions of Use and check box below to share full-text version of article.I have read and accept the Wiley Online Library Terms and Conditions of UseShareable LinkUse the link below to share a full-text version of this article with your friends and colleagues. Learn more.Copy URL Share a linkShare onFacebookTwitterLinkedInRedditWechat No abstract is available for this article. Volume14, Issue21May 24, 1983 RelatedInformation

ChemInform Abstract: SUCCESSIVE BECKMANN REARRANGEMENT‐ALKYLATION SEQUENCE BY ORGANOALUMINUM REAGENTS. SIMPLE ROUTE TO DL‐PUMILIOTOXIN C

Chemischer InformationsdienstVolume 13, Issue 11 Natural Products ChemInform Abstract: SUCCESSIVE BECKMANN REARRANGEMENT-ALKYLATION SEQUENCE BY ORGANOALUMINUM REAGENTS. SIMPLE ROUTE TO DL-PUMILIOTOXIN C K. HATTORI, K. HATTORISearch for more papers by this authorY. MATSUMURA, Y. MATSUMURASearch for more papers by this authorT. MIYAZAKI, T. MIYAZAKISearch for more papers by this authorK. MARUOKA, K. MARUOKASearch for more papers by this authorH. YAMAMOTO, H. YAMAMOTOSearch for more papers by this author K. HATTORI, K. HATTORISearch for more papers by this authorY. MATSUMURA, Y. MATSUMURASearch for more papers by this authorT. MIYAZAKI, T. MIYAZAKISearch for more papers by this authorK. MARUOKA, K. MARUOKASearch for more papers by this authorH. YAMAMOTO, H. YAMAMOTOSearch for more papers by this author First published: March 16, 1982 https://doi.org/10.1002/chin.198211344Read the full textAboutPDF ToolsRequest permissionExport citationAdd to favoritesTrack citation ShareShare Give accessShare full text accessShare full-text accessPlease review our Terms and Conditions of Use and check box below to share full-text version of article.I have read and accept the Wiley Online Library Terms and Conditions of UseShareable LinkUse the link below to share a full-text version of this article with your friends and colleagues. Learn more.Copy URL Share a linkShare onFacebookTwitterLinked InRedditWechat No abstract is available for this article. Volume13, Issue11March 16, 1982 RelatedInformation

REVIEW: ENVIRONMENTAL CHEMISTRY: AN OVERVIEW

Environmental Chemistry describes the world around us — a dynamic world of chemicals which become distributed between earth, water, atmosphere, and biota and transformed by natural reagents. The subject is far from new; until the age of synthetics, chemistry itself was based predominantly on the natural environment. Its present renaissance has been stimulated largely by the promise of assessment and control of toxic hazards and pollution, but the predictability, novel chemistry, and wide applications already apparent may prove at least as important. Just as synthetic chemistry revolutionized the lives of recent generations, environmental chemistry can provide a better future for all Earth's inhabitants.

Review: Environmental chemistry: An overview

Environmental Chemistry describes the world around us — a dynamic world of chemicals which become distributed between earth, water, atmosphere, and biota and transformed by natural reagents. The subject is far from new; until the age of synthetics, chemistry itself was based predominantly on the natural environment. Its present renaissance has been stimulated largely by the promise of assessment and control of toxic hazards and pollution, but the predictability, novel chemistry, and wide applications already apparent may prove at least as important. Just as synthetic chemistry revolutionized the lives of recent generations, environmental chemistry can provide a better future for all Earth's inhabitants.

ChemInform Abstract: POTENTIAL AFFINITY AND PHOTOAFFINITY REAGENTS FOR THE MEMBRANE PROTEIN OF HUMAN ERYTHROCYTES INVOLVED IN GLUCOSE TRANSPORT. SYNTHESIS OF 6‐AMINO‐6‐DEOXY DERIVATIVES OF D‐GLUCOSE

Chemischer InformationsdienstVolume 9, Issue 8 Natural Products ChemInform Abstract: POTENTIAL AFFINITY AND PHOTOAFFINITY REAGENTS FOR THE MEMBRANE PROTEIN OF HUMAN ERYTHROCYTES INVOLVED IN GLUCOSE TRANSPORT. SYNTHESIS OF 6-AMINO-6-DEOXY DERIVATIVES OF D-GLUCOSE M. RAMJEESINGH, M. RAMJEESINGHSearch for more papers by this authorA. KAHLENBERG, A. KAHLENBERGSearch for more papers by this author M. RAMJEESINGH, M. RAMJEESINGHSearch for more papers by this authorA. KAHLENBERG, A. KAHLENBERGSearch for more papers by this author First published: February 21, 1978 https://doi.org/10.1002/chin.197808315AboutPDF ToolsRequest permissionExport citationAdd to favoritesTrack citation ShareShare Give accessShare full text accessShare full-text accessPlease review our Terms and Conditions of Use and check box below to share full-text version of article.I have read and accept the Wiley Online Library Terms and Conditions of UseShareable LinkUse the link below to share a full-text version of this article with your friends and colleagues. Learn more.Copy URL Share a linkShare onFacebookTwitterLinkedInRedditWechat No abstract is available for this article. Volume9, Issue8February 21, 1978 RelatedInformation

ChemInform Abstract: PEPTIDE COUPLING REAGENTS, VIII. A HIGH YIELD PREPARATION OF PHENYL ESTERS OF AMINO ACIDS USING BENZOTRIAZOLYLOXYTRIS(DIMETHYLAMINO)PHOSPHONIUM HEXAFLUOROPHOSPHATE (BOP REAGENT)

Chemischer InformationsdienstVolume 8, Issue 39 Natural Products ChemInform Abstract: PEPTIDE COUPLING REAGENTS, VIII. A HIGH YIELD PREPARATION OF PHENYL ESTERS OF AMINO ACIDS USING BENZOTRIAZOLYLOXYTRIS(DIMETHYLAMINO)PHOSPHONIUM HEXAFLUOROPHOSPHATE (BOP REAGENT) B. CASTRO, B. CASTROSearch for more papers by this authorG. EVIN, G. EVINSearch for more papers by this authorC. SELVE, C. SELVESearch for more papers by this authorR. SEYER, R. SEYERSearch for more papers by this author B. CASTRO, B. CASTROSearch for more papers by this authorG. EVIN, G. EVINSearch for more papers by this authorC. SELVE, C. SELVESearch for more papers by this authorR. SEYER, R. SEYERSearch for more papers by this author First published: September 27, 1977 https://doi.org/10.1002/chin.197739355Read the full textAboutPDF ToolsRequest permissionExport citationAdd to favoritesTrack citation ShareShare Give accessShare full text accessShare full-text accessPlease review our Terms and Conditions of Use and check box below to share full-text version of article.I have read and accept the Wiley Online Library Terms and Conditions of UseShareable LinkUse the link below to share a full-text version of this article with your friends and colleagues. Learn more.Copy URL Share a linkShare onFacebookTwitterLinkedInRedditWechat No abstract is available for this article. Volume8, Issue39September 27, 1977 RelatedInformation

ChemInform Abstract: ARYLSULFONYLTETRAZOLES AS HIGHLY EFFICIENT CONDENSING REAGENTS FOR POLYNUCLEOTIDE SYNTHESIS

Chemischer InformationsdienstVolume 7, Issue 27 Natural Products ChemInform Abstract: ARYLSULFONYLTETRAZOLES AS HIGHLY EFFICIENT CONDENSING REAGENTS FOR POLYNUCLEOTIDE SYNTHESIS J. STAWINSKI, J. STAWINSKISearch for more papers by this authorT. HOZUMI, T. HOZUMISearch for more papers by this authorS. A. NARANG, S. A. NARANGSearch for more papers by this author J. STAWINSKI, J. STAWINSKISearch for more papers by this authorT. HOZUMI, T. HOZUMISearch for more papers by this authorS. A. NARANG, S. A. NARANGSearch for more papers by this author First published: July 6, 1976 https://doi.org/10.1002/chin.197627345Read the full textAboutPDF ToolsRequest permissionExport citationAdd to favoritesTrack citation ShareShare Give accessShare full text accessShare full-text accessPlease review our Terms and Conditions of Use and check box below to share full-text version of article.I have read and accept the Wiley Online Library Terms and Conditions of UseShareable LinkUse the link below to share a full-text version of this article with your friends and colleagues. Learn more.Copy URL Share a linkShare onFacebookTwitterLinked InRedditWechat No abstract is available for this article. Volume7, Issue27July 6, 1976 RelatedInformation

Relation of Sulphur to Variation in the Gravity of California Petroleum

Published in Petroleum Transactions, AIME, Volume 57, 1917, pages 989–1009. Introduction One of the features of oil-field work that puzzles operator, chemist, and geologist alike, is variation in the gravity of the petroleum produced on neighboring leases or even from adjoining wells. Few fields in the United States yield oil that is of uniform gravity throughout; in some fields the different grades are produced from different sands, in a few from different formations, and in many from different areas in the same sand. In a few cases, perhaps, a common assumption that the heavier oil is derived from the lighter through the escape of the more volatile constituents is valid, but many cases can not be explained in this way. Although in the California fields the specific gravity of the oil generally decreases with depth, there are numerous exceptions to this rule; and, as in many other regions the light oil is found nearest the surface, it is evident that evaporation underground is generally an unimportant factor. It is generally recognized that the great differences between petroleum from widely separated fields are due largely to differences in age and degree of metamorphism and to variation in the composition of the original organic matter; but in the writer's opinion some of these broader differences, as well as most of the minor variations in the character of the oil from any one field, are due to the local action of natural reagents such as sulphur or oxygen. This is particularly likely to be true if the oil has migrated from one formation to another, as in the California fields; and in some arcas it appears that variation in sulphur content may even afford a rough index of the extent or distance of the migration. It is the purpose of this paper to call attention to the chemical action of sulphur and oxygen on petroleum, to show that the gravity of the oil from any one field is intimately related to its sulphur content, and to discuss the possibility that oil in its migration will encounter and take up sulphur or oxygen. Petroleum chemists have been occupied so largely in working out the complex constitution of petroleum and the processes of refining it, that we know little of the effect on petroleum of any of the substances with which it comes in contact underground. The study of petroleum from the geochemical standpoint has received slight attention except from a few chemists, and it is therefore impossible to trace in detail the natural changes that oil may undergo. Clifford Richardson however, pointed out many years ago the influence of sulphur in hardening asphalt. T.P. 057–48