- Electrophilic Substitution of Hydrogen in Betulin and Diacetylbetulin
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Betulin and diacetylbetulin, which can be regarded as sterically hindered alkenes, reacted with N-chloro-, N-bromo-, and N-iodosuccinimides to give products of allylic and vinylic substitution in quantitative overall yield. The contribution of allylic substitution increases in the series Cl Br I. Quantum chemical simulation of the reactions of diacetylbetulin with N-halosuccinimides showed that, regardless of the electrophile power, all reactions involve open-chain carbocationic intermediates. The direction of deprotonation of the latter with formation of allylic or vinylic substitution products is determined by preferential orientation of the vacant orbital and C–Hlg bond.
- Bodrikov,Kurskii, Yu. A.,Chiyanov,Subbotin, A. Yu.
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- N-Chlorination rate of five-membered heterocyclic nitrogen compounds
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The kinetics of N-chlorination reaction of pyrrolidine, pyrrolidone, succinimide, 5,5,-dimethyloxazolidine-2,4-dione, 5,5-dimethylhydantoin and 1-hydroximethyl-5,5-dimethylhydantoin with HOCl in aqueous solution were studied at 25 °C, constant ionic strength and under isolation conditions in a wide pH range. The set of compounds studied in this paper is characterized by having different functional groups and the same cyclic structure, consisting of a five-member ring with a nitrogen atom in the ring, which is susceptible to be chlorinated. This series of compounds covers nine pKa units, and the kinetic studies allow us to know, like, the presence of an amino, amide or imide group modify the reactivity of nitrogenous compound. Experimental data were fitted to the first-order kinetic equation. All reactions were found to be of first order in both HOCl and nitrogenous compound concentration. Kinetics studies demonstrate that some of these compounds are hydrolyzed in alkaline medium. In each case, reaction mechanism in agreement with the experimental results is proposed. The results were compared with other compounds with similar cyclic structure (2-oxazolidinone and proline). Copyright
- Pastoriza, Cristina,Antelo, Juan Manuel,Amoedo, Francisco Andrés,Parajó, Mercedes
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- CYCLOBUTYL AMIDE MONOACYLGLYCEROL LIPASE MODULATORS
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Compounds of Formula (I), and pharmaceutically acceptable salts, isotopes, N-oxides, solvates, and stereoisomers thereof, pharmaceutical compositions containing them, methods of making them, and methods of using them including methods for treating disease states, disorders, and conditions associated with MGL modulation, such as those associated with pain, psychiatric disorders, neurological disorders (including, but not limited to depression, major depressive disorder, treatment resistant depression, anxious depression, autism spectrum disorders, Asperger syndrome, and bipolar disorder), cancers and eye conditions: wherein R1, , R3, and L are as defined herein.
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- 4-(IMIDAZO[1,2-A]PYRIDIN-3-YL) -PYRIMIDINE DERIVATIVES
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Compounds of the formula (I) in which R1, R2, V, X, Y and Z have the meanings indicated in Claim 1, are inhibitors of c-Kit kinase, and can be employed for the treatment of cancer.
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Page/Page column 159-160
(2021/01/29)
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- Convenient and environment-friendly synthesis of sulfonyl chlorides from S -alkylisothiourea salts via N-chlorosuccinimide chlorosulfonation
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A convenient, practical, and environmentally friendly method for the synthesis of sulfonyl chlorides has been developed. Structurally diverse sulfonyl chlorides were synthesized in moderate to excellent yields from S-alkylisothiourea salts, which can be easily prepared from readily accessible alkyl halides or mesylates and inexpensive thiourea, via N-chlorosuccinimide chlorosulfonation. In large-scale syntheses, the byproduct succinimide from 'waste water' can be conveniently converted into the starting reagent N-chlorosuccinimide with sodium hypochlorite (bleach) to make the method sustainable. Georg Thieme Verlag Stuttgart, New York.
- Yang, Zhanhui,Xu, Jiaxi
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p. 1675 - 1682
(2013/07/27)
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- Preparation of several active N-chloro compounds from trichloroisocyanuric acid
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A very simple method for the preparation of several activeN-chloro compounds that have extensive applications in organic synthesis, industry, and medicine has been developed.Tetrachloroglycolurils, chloramine-T, N-chlorosaccharin, N-chlorosuccinimide, N-chlorophthalimide, N,N￠-dichlorophenobarbital,and N,N￠-dichlorobarbital were synthesized by chlorination with trichloroisocyanuric acid under mild reaction conditions at roomtemperature. This method is clean, fast, and efficient; the yields are also good to excellent. Georg Thieme Verlag Stuttgart.
- Shiri, Azam,Khoramabadi-Zad, Ahmad
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experimental part
p. 2797 - 2801
(2010/01/21)
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- Conversion of nucleophilic halides to electrophilic halides: Efficient and selective halogenation of azinones, amides, and carbonyl compounds using metal halide/lead tetraacetate
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AlCl3/Pb(OAc)4 and ZnBr2/Pb(OAc) 4 are efficient electrophilic N- and α-C-halogenating agents. A variety of azinones, amides and carbonyl compounds were chemoselectively and regioselectively N-, or α-C-halogenated in good to excellent yield using AlCl3/Pb(OAc)4 and ZnBr2/Pb(OAc)4 in acetonitrile. Georg Thieme Verlag Stuttgart.
- Kim, Jeum-Jong,Kweon, Deok-Heon,Cho, Su-Dong,Kim, Ho-Kyun,Lee, Sang-Gyeong,Yoon, Yong-Jin
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p. 194 - 200
(2007/10/03)
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- Xanthine derivatives as DPP-IV inhibitors
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The present invention provides novel compounds exhibiting an excellent DPPIV inhibition effect. The compounds are represented by the formula: wherein, m is 0 or 1; n is 0; R31, R32, R33, R34, R35, R36, R37, R38, R39, R40, R41, and R42 each represent a hydrogen atom; X represents an alkynyl group, an aryl group, and such, which group may be substituted; and, R1 and R2 each independently represents a hydrogen atom, an alkyl group, an alkoxyl group, or such, or salts or hydrates thereof.
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- Metal salt catalyzed process to oxazolines and subsequent formation of chloroketones
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This invention relates to a process for the preparation of an α-chloroketone compound comprising the steps of (i) cyclizing an alkynyl amide to form a 5-methyleneoxazoline STR1 (ii) chlorinating the 5-methyleneoxazoline using trichlorolsocyanuric acid to produce a chlorinated oxazoline intermediate STR2 and (iii) hydrolyzing the chlorinated oxazoline intermediate with an aqueous acid to produce the desired monochloroketone STR3 wherein Z is alkyl or substituted alkyl, aryl or substituted aryl, heteroaryl or substituted heteroaryl or phenylene, R is a hydrogen atom or alkyl, and R1 and R2 are each independently an alkyl or substituted alkyl group, or R1 and R2 together with the carbon atom to which they are attached form a cyclic structure. Additionally, when R is a hydrogen atom, a dichloroketone can be conveniently formed through adjustment of reaction conditions.
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- Synthesis and solid state and solution characterization of mono- and di-(η1-C) carbamoyl-palladium complexes. New efficient palladium-catalyzed routes to carbamoyl chlorides: Key intermediates to isocyanates, carbamic esters, and ureas
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The catalytic conversion of primary and secondary amines into isocyanates or carbamoyl chlorides is performed using palladium complexes. The palladium-based catalytic systems is very active and avoids the synthesis of phosgene. The palladium (II) complex
- Aresta, Michele,Giannoccaro, Potenzo,Tommasi, Immacolata,Dibenedetto, Angela,Lanfredi, Anna Maria Manotti,Ugozzoli, Franco
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p. 3879 - 3889
(2008/10/08)
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- Process to chloroketones using oxazolines
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This invention relates to a process for the preparation of an α-chloroketone compound comprising the steps of (i) cyclizing an alkynyl amide to form a 5-methyleneoxazoline STR1 (ii) chlorinating the 5-methyleneoxazoline using trichloroisocyanuric acid to produce a chlorinated oxazoline intermediate STR2 and (iii) hydrolyzing the chlorinated oxazoline intermediate with an aqueous acid to produce the desired monochloroketone STR3 wherein Z is alkyl or substituted alkyl, aryl or substituted aryl, heteroaryl or substituted heteroaryl or phenylene, R is a hydrogen atom or alkyl, and R1 and R2 are each independently an alkyl or substituted alkyl group, or R1 and R2 together with the carbon atom to which they are attached form a cyclic structure. Additionally, when R is a hydrogen atom, a dichloroketone can be conveniently formed through adjustment of reaction conditions.
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- Process to chloroketones using oxazolines
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This invention relates to a process for the preparation of an α-chloroketone compound comprising the steps of (i) cyclizing an alkynyl amide to form a 5-methyleneoxazoline STR1 (ii) chlorinating the 5-methyleneoxazoline using trichloroisocyanuric acid to produce a chlorinated oxazoline intermediate STR2 and (iii) hydrolyzing the chlorinated oxazoline intermediate with an aqueous acid to produce the desired monochloroketone STR3 wherein Z is alkyl or substituted alkyl, aryl or substituted aryl, heteroaryl or substituted heteroaryl or phenylene, R is a hydrogen atom or alkyl, and R1 and R2 are each independently an alkyl or substituted alkyl group, or R1 and R2 together with the carbon atom to which they are attached form a cyclic structure. Additionally, when R is a hydrogen atom, a dichloroketone can be conveniently formed through adjustment of reaction conditions.
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- Metal salt catalyzed process to oxazolines and subsequent formation of chloroketones
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This invention relates to a process for the preparation of an α-chloroketone compound comprising the steps of (i) cyclizing an alkynyl amide to form a 5-methyleneoxazoline (ii) chlorinating the 5-methyleneoxazoline using trichloroisocyanuric acid to produce a chlorinated oxazoline intermediate and (iii) hydrolyzing the chlorinated oxazoline intermediate with an aqueous acid to produce the desired monochloroketone wherein Z is alkyl or substituted alkyl, aryl or substituted aryl, heteroaryl or substituted heteroaryl or phenylene, R is a hydrogen atom or alkyl, and R1and R2are each independently an alkyl or substituted alkyl group, or R1and R2together with the carbon atom to which they are attached form a cyclic structure. Additionally, when R is a hydrogen atom, a dichloroketone can be conveniently formed through adjustment of reaction conditions.
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- Process for the preparation of chloroketones using oxazolines
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This invention relates to a process for the preparation of an α-chloroketone compound comprising the steps of (i) cyclizing an alkynyl amide to form a 5-methyleneoxazoline (ii) chlorinating the 5-methyleneoxazoline using trichloroisocyanuric acid to produce a chlorinated oxazoline intermediate and (iii) hydrolyzing the chlorinated oxazoline intermediate with an aqueous acid to produce the desired monochloroketone wherein Z is alkyl or substituted alkyl, aryl or substituted aryl, heteroaryl or substituted heteroaryl or phenylene, R is a hydrogen atom or alkyl, and R1and R2are each independently an alkyl or substituted alkyl group, or R1and R2together with the carbon atom to which they are attached form a cyclic structure. Additionally, when R is a hydrogen atom, a dichloroketone can be conveniently formed through adjustment of reaction conditions.
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- ANGIOTENSIN II RECEPTOR BLOCKING IMIDAZOLES
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Substituted imidazoles such as STR1 are useful as angiotensin II blockers. These compounds have activity in treating hypertension and congestive heart failure.
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- Treatment of congestive heart failure with angiotensin 11 receptor blocking imidazoles
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Substituted imidazoles such as STR1 are useful as angiotensin II blockers. These compounds have activity in treating hypertension and congestive heart failure.
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- 19,11 β-bridged steroids, their manufacture and pharmaceutical preparations containing them
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New 19,11β-bridged steroids of the general formula I STR1 where R1 stands for a methyl or ethyl radical, R2 for a hydrogen or chlorine atom or a C1 -C4 -alkyl radical, B and G, which are the same or different, respectively for a hydrogen atom, a C1 -C4 -alkyl radical or, together, for a second bond between the carbon atoms 6 and 7, B and R2 together for a methylene or an ethylene group, Z for the radical of a pentagonal or hexagonal ring, which is possibly substituted and possibly unsaturated, V stands for a possibly substituted carbocyclic or heterocyclic aryl radical, the ring A for STR2 M and N together meaning a second bond or M a hydrogen atom and N a hydroxy group, X means an oxygen atom, two hydrogen atoms or a hydroxyimino grouping N?OH, R3 and D, which are the same or different, respectively a hydrogen atom, a nitrile radical or a C1 -C4 -alkyl radical or, together, a methylene or ethylene group, E a hydrogen atom or a C1 -C4 -alkyl radical, D and E together meaning a second bond between carbon atoms 1 and 2 or together a methylene group STR3 with R11 in the meaning of a hydrogen atom or a C1 -C8 -alkyl radical, are described as well as their pharmaceutically tolerated addition salts with acids. The new compounds possess valuable pharmacological properties.
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- Etude cinetique de la N-chloration de la succinimide en phase aqueuse
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A kinetic study of the N-chlorination, in aqueous medium, of succinimide (SH) at low pH ( 9) is presented.We have derived the rate constants and activation energies of the processes involved.A stopped-flow spectrophotometric technique was used to study the kinetics.Without chloride ions, our experimental results can be interpreted by two kinetically indistinguishable mechanisms: SH + ClO- k2/-> products; S- + HClO k3/-> products The limiting values of the rate constants for the case in which only one process is involved in the kinetics of chlorination were evaluated: k20 = 1.6 x 105 M-1 s-1 at 293 K; k30 = 2.2 x 107 M-1 s-1 at 293 K.In acid medium, in the presence of chloride ions, we observe a nucleophilic attack of the S- ion on molecular chlorine Cl2.This process is added to the two former processes.
- Matte, Denise,Solastiouk, Bernard,Merlin, Andre,Deglise, Xavier
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- Side chain chlorination process of heterocycles
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A novel method of chlorinating the alkyl side chains of a nitrogen containing heterocyclic comprising reacting an alkyl substituted heterocycle with trichloroisocyanuric acid at temperatures of 20° to 200° C. to obtain the same in high yields.
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- Process for 2-chlorosulfinylazetidin-4-ones
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Penicillin sulfoxide esters having the sulfoxide group in the α-configuration are reacted with an N-chloro halogenating agent at a temperature between about 70° C. and about 120° C. in the presence of an alkylene oxide and preferably also calcium oxide to produce 2-chlorosulfinyl-azetidin-4-one intermediates. The chlorosulfinyl intermediates are then treated with a Friedel-Crafts catalyst, for example, stannic chloride to provide a 3-exomethylenecepham β-sulfoxide. The latter compounds are useful in the preparation of 3-alkoxy and 3-halo substituted cephalosporin antibiotic compounds.
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- Process for production of 6-aminopenicillanic acid or 7-aminocephalosporanic acid derivatives
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A derivative of 6-aminopenicillanic acid or 7-aminocephalosporanic acid is produced by a process which comprises chlorinating or brominating a 6-thioacylaminopenicillanic acid or 7-thioacylaminocephalosporanic acid compound to obtain a corresponding iminothiohalide compound, and then solvolyzing the iminothiohalide compound. The process is novel and industrially feasible for producing the amino compound, which is not accompanied by "reconversion reaction".
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