- Adapting decarbonylation chemistry for the development of prodrugs capable ofin vivodelivery of carbon monoxide utilizing sweeteners as carrier molecules
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Carbon monoxide as an endogenous signaling molecule exhibits pharmacological efficacy in various animal models of organ injury. To address the difficulty in using CO gas as a therapeutic agent for widespread applications, we are interested in developing CO prodrugs through bioreversible caging of CO in an organic compound. Specifically, we have explored the decarboxylation-decarbonylation chemistry of 1,2-dicarbonyl compounds. Examination and optimization of factors favorable for maximal CO release under physiological conditions led to organic CO prodrugs using non-calorific sweeteners as leaving groups attached to the 1,2-dicarbonyl core. Attaching a leaving group with appropriate properties promotes the desired hydrolysis-decarboxylation-decarbonylation sequence of reactions that leads to CO generation. One such CO prodrug was selected to recapitulate the anti-inflammatory effects of CO against LPS-induced TNF-α production in cell culture studies. Oral administration in mice elevated COHb levels to the safe and efficacious levels established in various preclinical and clinical studies. Furthermore, its pharmacological efficacy was demonstrated in mouse models of acute kidney injury. These studies demonstrate the potential of these prodrugs with benign carriers as orally active CO-based therapeutics. This represents the very first example of orally active organic CO prodrugs with a benign carrier that is an FDA-approved sweetener with demonstrated safety profilesin vivo.
- Brewer, Maya,Cachuela, Alyssa,De La Cruz, Ladie Kimberly,Gallo, David,Ji, Xingyue,Lu, Wen,Menshikh, Anna,Otterbein, Leo,Tan, Chalet,Wang, Binghe,Wang, Minjia,Wang, Siming,Yang, Haichun,Yang, Xiaoxiao,de Caestecker, Mark
-
p. 10649 - 10654
(2021/08/20)
-
- Synthesis, characterization and antimicrobial evaluation of new 3-(Alkyl/Arylamino)benzo[d]isothiazole 1,1-derivatives
-
The saccharine nucleus has long been recognized as a significant component in medicine. A series of pseudo-saccharine amines derivatives (7a-j) were synthesized and examined for their antibacterial activity. After testing all compounds, 7b, 7f, 7g, 7i and 7j were found most effective against Escherichia coli, Streptococcus aureus and Bacillus subtilis strains. The MIC of the compound was found from 4.6 to 16.1 μM. Further, compound 7f and 7i exhibited excellent activity against E.coli and Bacillus subtilis with MIC value 4.6 and 4.7 μM respectively. The compound 7b and 7i was found active against all the three bacteria. The zone inhibition was observed at 10 μM against Escherichia coli, Staphylococcus aureus and Bacillus subtilis at 0.9, 1.8, 3.9 respectively for 7b and 1.0, 1.8 and 2.0 cm respectively for 7i.
- Kamble, Dhanraj P.,Shankarwar, Anil G.,Mane, Yogesh D.,Tigote, Radhakrishna M.,Sarnikar, Yuvaraj P.,Madje, Balaji R.
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p. 797 - 804
(2021/09/08)
-
- Preparation method of saccharin
-
The invention discloses a preparation method of saccharin. The invention provides a preparation method of saccharin as shown in a formula 1 represented in the specification. The preparation method ischaracterized by comprising the following step: in water, in the presence of tungstate and/or tungstic acid, carrying out oxidation reaction on a compound shown in a formula 2 and hydrogen peroxide toobtain saccharin shown in a formula 1.
- -
-
Paragraph 0128-0137; 0140-0151
(2020/10/14)
-
- Synthetic method for preparing saccharin (by machine translation)
-
1,2 - Benzisothiazol -3 - ketone compounds are subjected to an oxidation reaction with an oxidizing agent, and an oxidizing agent oxidizes thioether of 1,2 - benzisothiazol -3 -one compound to thioamide to obtain the O-benzoyl sulfamide compound. Compared with the traditional production technology of saccharin, the saccharin synthesis method has the advantages of simple process, low cost, high separation efficiency, low pollution and the like, and accords with the green chemistry. (by machine translation)
- -
-
Paragraph 0033-0076; 0081-0090
(2020/07/02)
-
- CARBON MONOXIDE PRODRUGS FOR THE TREATMENT OF MEDICAL DISORDERS
-
The present invention provides new compounds and compositions thereof that release carbon monoxide for the treatment of medical disorders that are responsive to carbon monoxide, for example, inflammatory, pain, and dermatological disorders.
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-
Page/Page column 128-131
(2020/05/21)
-
- Method for removing saccharin in probenazole
-
The invention provides a method for removing saccharin in probenazole. The method comprises the steps: the probenazole containing saccharin impurities is suspended in an appropriate amount of water, then sodium bicarbonate or potassium bicarbonate is continuously added till no gas is generated, then centrifuge dripping is conducted, drip washing is conducted through an appropriate amount of water,and thus the saccharin in the probenazole can be removed. A water solution containing saccharin sodium is acidized, and then the saccharin can be recovered. The method is easy and convenient to operate, an organic solvent is not adopted, the three wastes (waste gas, waste water and industrial residue) are less, safety and environmental protection are achieved, an obtained product is high in purity, the production cost and the environmental protection cost are greatly saved, and industrialization is easy to achieve.
- -
-
Paragraph 0018-0027
(2020/02/17)
-
- Preparation method of saccharin by using enhanced oxidation process of o-toluene sulfonamide
-
The present invention relates to a saccharin manufacturing method using an improved oxidation process of toluene sulfonamide, and more specifically, capable of economically and efficiently manufacturing saccharin through an efficient oxidation reaction of o-toluene sulfonamide using CrO_3 and H_5IO_6. The present invention is provided to improve a conventional method having a disadvantage of high costs in the oxidation reaction of the o-toluene sulfonamide such that it is possible to economically manufacture saccharin in a high yield.COPYRIGHT KIPO 2018
- -
-
Paragraph 0045-0047; 0067
(2018/08/19)
-
- Aromatic Chlorosulfonylation by Photoredox Catalysis
-
Visible-light photoredox catalysis enables the efficient synthesis of arenesulfonyl chlorides from anilines. The new protocol involves the convenient in situ preparation of arenediazonium salts (from anilines) and the reactive gases SO2and HCl (from aqueous SOCl2). The photocatalytic chlorosulfonylation operates at mild conditions (room temperature, acetonitrile/water) with low catalyst loading. Various functional groups are tolerated (e.g., halides, azides, nitro groups, CF3, SF5, esters, heteroarenes). Theoretical and experimental studies support a photoredox-catalysis mechanism.
- Májek, Michal,Neumeier, Michael,Jacobi von Wangelin, Axel
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p. 151 - 155
(2017/01/17)
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- A kind of processing adjacent sulfonaide method of crystallization mother liquor benzoic acid methyl ester
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The invention relates to a method for treating a methyl 2-(aminosulfonyl)benzoate crystallization mother solution, which comprises the following steps: performing chemical reaction on sodium hydroxide or a sodium hydroxide solution or potassium hydroxide or calcium hydroxide or calcium oxide and a methyl 2-(aminosulfonyl)benzoate crystallization mother solution generated in the concentration, crystallization or purification process during methyl 2-(aminosulfonyl)benzoate production, thus generating saccharin salt; heating to distill out methanol, cooling to 30 DEG C or below, and adding water until the Baume degree is regulated to 12Be or below; and filtering, and adding acid into the filtrate until the pH value is 1.0-2.0 to precipitate insoluble saccharin, wherein the recovered insoluble saccharin can be used as a raw material for methyl 2-(aminosulfonyl)benzoate production or saccharin sodium production. The production process of the treatment method is simple and quick in reaction and simple to operate, can lower the production cost, reduce organic substances in effluent waste water and lower the sewage treatment cost, and also can reduce environmental pollution, thereby being beneficial to environmental protection.
- -
-
Paragraph 0022; 0023
(2017/01/23)
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- The Construction of 3-Methyl-4-arylpiperidines via a trans- Perhydroindolic Acid-Catalyzed Asymmetric Aza-Diels-Alder Reaction
-
An efficient trans-perhydroindolic acid-catalyzed asymmetric aza-Diels-Alder reaction of cyclic 1-azadienes and propanal was developed for the synthesis of chiral 3-methyl-4-aryldehydropiperidine derivatives (up to 98% yield and 99% ee). Such scaffolds are often found in bioactive compounds and medicines. A gram-scale reaction was carried out with a low catalyst loading to give the desired product in high yield and with excellent enantioselectivity. The resulting dehydropiperidine derivatives can be further transformed to chiral 3-methyl-4-aryl-substituted piperidines with high efficiency.
- An, Qianjin,Shen, Jiefeng,Butt, Nicholas,Liu, Delong,Liu, Yangang,Zhang, Wanbin
-
supporting information
p. 3627 - 3638
(2016/01/25)
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- A recyclable CO surrogate in regioselective alkoxycarbonylation of alkenes: Indirect use of carbon dioxide
-
Herein, we report a Pd-catalysed alkoxycarbonylation of alkenes based on the use of a recyclable CO2 reduction product, the crystalline and air-stable N-formylsaccharin, as a CO surrogate. The carbonylation proceeds under ambient conditions in an exceptionally complementary regioselective fashion yielding the desired branched products from styrene derivatives and valuable linear esters from alkyl-substituted alkenes.
- Gehrtz,Hirschbeck,Fleischer
-
supporting information
p. 12574 - 12577
(2015/08/06)
-
- Tosvinyl and besvinyl as protecting groups of imides, azinones, nucleosides, sultams, and lactams. Catalytic conjugate additions to tosylacetylene
-
The use of the 2-(4-methylphenylsulfonyl)-ethenyl (tosvinyl, Tsv) group for the protection of the NH group of a series of imides, azinones (including AZT), inosines, and cyclic sulfonamides has been examined. The Tsvprotected derivatives are obtained in excellent yields by conjugate addition to tosylacetylene (ethynyl p-tolyl sulfone). The stereochemistry of the double bond can be controlled at will: with only 1 mol % of Et3N or with catalytic amounts of NaH, the Z stereoisomers are generated almost exclusively, while the E isomers are obtained using a stoichiometric amount of DMAP. Analogous phenylsulfonylvinyl-protected groups (with the besvinyl or Bsv group instead of Tsv) are obtained stereospecifically by reaction with (Z)- or (E)-bis(phenylsulfonyl)ethene. For lactams and oxazolidinones, this last method is much better. The Tsv and Bsv groups are stable in the presence of non-nucleophilic bases and to acids. They can be removed highly effectively via a conjugate addition-elimination mechanism using pyrrolidine or sodium dodecanethiolate as nucleophiles.
- Petit, Elena,Bosch, Llus,Font, Joan,Mola, Laura,Costa, Anna M.,Vilarrasa, Jaume
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p. 8826 - 8834
(2015/01/08)
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- Palladium-catalyzed reductive carbonylation of aryl halides with N-formylsaccharin as a CO source
-
Easy peasy: The title reaction employs N-formylsaccharin, which is an easily accessible crystalline compound, as an effective CO source. The reactions proceed with a small excess of the CO source at moderate temperatures and were successfully applied to a wide range of aryl bromides. DMF=N,N- dimethylformamide, dppb=1,4-bis-(diphenylphosphino)butane. Copyright
- Ueda, Tsuyoshi,Konishi, Hideyuki,Manabe, Kei
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p. 8611 - 8615
(2013/09/12)
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- Palladium-catalyzed fluorocarbonylation using N-formylsaccharin as CO source: General access to carboxylic acid derivatives
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N-Formylsaccharin, an easily accessible crystalline compound, has been employed as an efficient CO source in Pd-catalyzed fluorocarbonylation of aryl halides to afford the corresponding acyl fluorides in high yields. The reactions use a near-stoichiometric amount of the CO source (1.2 equiv) and tolerate diverse functional groups. The acyl fluorides obtained could be readily transformed into various carboxylic acid derivatives such as carboxylic acid, esters, thioesters, and amides in a one-pot procedure.
- Ueda, Tsuyoshi,Konishi, Hideyuki,Manabe, Kei
-
supporting information
p. 5370 - 5373
(2013/11/06)
-
- METHOD AND PRODUCT
-
The present invention provides a method of producing a co-crystal, the method comprising the steps of providing a first substance and a second substance, wherein the first and second substances are compatible to form a co-crystal, mixing said first and second substances together, and exposing the mixture of said first and second substances to prolonged and sustained conditions of pressure and shear, sufficient to form a co-crystal of said first and second substance. The prolonged and sustained conditions of pressure and shear are preferably applied in an extrusion process. Associated compositions and uses thereof are also provided.
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-
- Studies of silyl-transfer photochemical reactions of N-[(trimethylsilyl) alkyl]saccharins
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Photochemical studies of N-[(trimethylsilyl)alkyl]saccharins were carried out to investigate their photochemical behavior. Depending on the nature of the substrate and the solvent system employed, reactions of these substances can take place by either SET-promoted silyl migration from carbon to either the amide carbonyl or sulfonyl oxygen or by a N-S homolysis route. The results of the current studies show that an azomethine ylide, arising from a SET-promoted silyl migration pathway, is generated in photoreactions of N-[(trimethylsilyl) methyl]saccharin and this intermediate reacts to give various photoproducts depending on the conditions employed. In addition, irradiation of N-[(trimethylsily)ethyl]saccharin produces an excited state that reacts through two pathways, the relative importance is governed by solvent polarity and protic nature. Finally, photoirradiation of N-[(trimethylsilyl)propyl]saccharin in a highly polar solvent system comprised of 35% aqueous MeOH gives rise to formation of a tricyclic pyrrolizidine and saccharin that generated via competitive SET-promoted silyl transfer and γ-hydrogen abstraction pathways.
- Cho, Dae Won,Oh, Sun Wha,Kim, Dong Uk,Park, Hea Jung,Xue, Jin Ying,Yoon, Ung Chan,Mariano, Patrick S.
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experimental part
p. 2453 - 2458
(2010/11/17)
-
- TiCl4-promoted direct N-acylation of sulfonamide with carboxylic ester
-
Several Lewis acids were investigated as promoters in the intermolecular or intramolecular direct N-acylation reaction of sulfonamides using carboxylic ester as an acylating agent. TiCl4 was found to possess the highest activity and enhanced efficiently sulfonamide to form N-acylsulfonamides under optimized conditions. This method provides a novel approach to make N-acylsulfonamides from ester via an easy work-up procedure.
- Fu, Shaomin,Lian, Xiaoyan,Ma, Tongmei,Chen, Wenhua,Zheng, Meifang,Zeng, Wei
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supporting information; experimental part
p. 5834 - 5837
(2010/11/04)
-
- Reaction co-crystallization of molecular complexes or co-crystals
-
Multi-component crystals (co-crystals) are prepared by combining co-crystal components in non-stoichiometric concentrations in solution. The solubility of the molecular complex in the solvent is reduced, increasing the probability that the molecular complex is the least soluble form in the system, upon which it precipitates. A crystalline product is produced without the need for grinding, solvent evaporation, or temperature variation.
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- Oxidative cyclization of N-alkyl-o-methyl-arenesulfonamides to biologically important saccharin derivatives
-
Various biologically important saccharin skeletons and their N-alkyl derivatives have been efficiently prepared by chromium(VI) oxide catalyzed H5IO6 oxidation of N-alkyl-o-methyl-arenesulfonamides in acetonitrile. N-tert-Butyl saccharin skeletons were easily prepared by H5IO6-CrO3 oxidation of N-tert-butyl-o-methyl arenesulfonamides in the presence of acetic anhydride. The method that furnished the novel fluoro and trifluoromethyl substituted saccharin skeletons is characterized by two steps, a simple work-up procedure, a single purification and good overall yields from substituted toluene derivatives.
- Xu, Liang,Shu, Hong,Liu, Ying,Zhang, Suhong,Trudell, Mark L.
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p. 7902 - 7910
(2007/10/03)
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- Chromium(VI) oxide catalyzed oxidation of sulfides to sulfones with periodic acid
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A highly efficient and selective oxidation of sulfides to sulfones with periodic acid catalyzed by CrO3 is described. A variety of electron-rich and electron-deficient sulfides were oxidized to sulfones with 2 mol% CrO3 in acetonitrile at room temperature in excellent yields. Sulfides with other readily oxidized functional groups were selectively oxidized to sulfones in high yields with 10 mol% CrO3 in ethyl acetate/acetonitrile at -35 °C.
- Xu, Liang,Cheng, Jie,Trudell, Mark L.
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p. 5388 - 5391
(2007/10/03)
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- Cleansing or cosmetic compositions comprising zinc alkylsulphates and/or alky(poly)ethoxysulphates as surfactants and preservatives
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The invention relates to a cleansing or cosmetic composition having self-preservative properties, comprising, as a surfactant and preservative, at least one compound of the general formula:R-(OCH2CH2)m-OSO3-· ?Zn2+ in which R is saturated or unsaturated, branched or linear C3-C22 alkyl and m may vary from 0 to 20,the composition being free of other preservatives or comprising at least one other preservative at a concentration which is ineffective and/or not sufficient to confer the desired characteristics of preservability in an analogous or similar composition which does not contain the said compound.
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-
-
- Sulfur Oxidation Mediated by Imine Derivatives
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A number of oxime and benzothiazoline derivatives have been prepared and examined as mediators of sulfur oxidation by hydrogen peroxide as oxidant in the presence of base.In all cases, sulfoxidation was observed in the presence of the mediators, whereas negligible reaction occured in the absence of mediators.Carbodiimides were also examined as mediators; they proved to be highly reactive, providing predominant oxidation directly to sulfone.
- Page, Philip C. Bulman,Bethell, Donald,Stocks, Paul A.,Heer, Jag P.,Graham, Andrew E.,et al.
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p. 1355 - 1358
(2007/10/03)
-
- Phototransformation of Chlorimuron-ethyl in Aqueous Solution
-
Chlorimuron-ethyl is relatively stable in water buffered to pH 7.0 and 9.0, but hydrolyzes readily (half-life, 14 d) in water buffered to pH 4.0. In addition, chlorimuron-ethyl photodegrades rapidly and extensively in aqueous solution. The predominant photoproducts are 4-methoxy-6-chloro-2-aminopyrimidine, ethyl 2-aminosulfonylbenzoate, N-(4-methoxy-6-chloropyrimidin-2-yl)methyl urea, and o-benzoic sulfimide (saccharin). A minor deesterified product (chlorimuron) was evident. The decrease in chlorimuron-ethyl concentration in aqueous solutions followed first-order kinetics. The rate of degradation in different types of water followed the order irrigation water > tap water > distilled water. Chlorimuron-ethyl photodegraded in pH 4, 7, and 9 buffer solutions under both UV and sunlight. A faster degradation rate in pH 4.0 buffer solution was observed.
- Choudhury, Partha P.,Dureja, Prem
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p. 3379 - 3382
(2007/10/03)
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- Alkoxide-induced reactions of N-substituted saccharins. Synthesis of 1,2-benzothiazocine 1,1-dioxide and 2,3-dihydropyrrolo[1,2-b]-[1,2]benzisothiazole 5,5-dioxide derivatives
-
The reactions of saccharin derivatives 1 with sodium alkoxides were studied. Under mild conditions, compounds 1a-f gave the corresponding open sulfonamides 5a-f. Under drastic conditions, β-(saccharin-2)propionic acid derivatives 1a,b reacted with sodium ethoxide affording saccharin and β-ethoxypropionic acid derivatives 4a,b. γ-(Saccharin-2)butyric acid derivatives 1c,d and γ-(saccharin-2)butyrophenone 1f reacted with sodium t-butoxide in dimethyl sulfoxide affording 5-substituted 6-hydroxy-3,4-dihydro-2H-1,2-benzothiazocine 1,1-dioxides 9. From mother liquors, 1-substituted 2,3-dihydropyrrolo[1,2-b][1,2]benzisothiazole 5,5-dioxides 10 were isolated several hours later, though not detected immediately after completing the reaction. When the reactions were carried out in t-butyl alcohol, the yields of 9 diminished and those of 10 increased with product ratio inversion. Different expermental observations on the possible pathway generating 9 and 10 are discussed.
- Blanco,Perillo,Schapira
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p. 145 - 154
(2007/10/02)
-
- SACCHARIN DERIVATIVE PROTEOLYTIC ENZYME INHIBITORS
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Compounds having the structural formula STR1 which inhibit the enzymatic activity of proteolytic enzymes, and processes for preparation thereof, method of use thereof in treatment of degenerative diseases and pharmaceutical compositions thereof are disclosed.
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-
-
- New medicament aerosol formulation based on fusafungine
-
New medicament aerosol formulation based on fusafungine comprising excipient which is either dimethyl isosorbide or preferably, isopropyl myristate, and using as propellant 1,1,1,2-tetrafluoroethane.
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-
- A prodrug approach to increasing the oral potency of a phenolic drug. 1. Synthesis, characterization, and stability of an O-(imidomethyl) derivative of 17β-estradiol
-
An O-(saccharinylmethyl) prodrug was synthesized to improve the poor oral potency of the phenolic drug 17β-estradiol. This O-(imidomethyl) type of prodrug was designed to undergo chemical hydrolysis and to be a poor substrate for enzymatic hydrolysis. At 37 °C, it was found to exhibit half- lives of about 13 min in 50% methanol:pH 7.0 (v/v) phosphate buffer, about 3 min in rat plasma, about 15 min in human plasma, and about 50 min in 20% rat liver homogenate. Introduction of the enzyme poison tetraethyl pyrophosphate or the protein denaturant sodium fluoride into rat plasma had no significant effect on the half-life. Thus, the observed increased rate of hydrolysis in biological media is not due to enzymatic catalysis but to a nonspecific solventlike effect. The fact that the rate of hydrolysis in the methanol:buffer exhibited a first-order dependence on the hydroxide ion concentration and that the rate of hydrolysis increased with increasing methanol concentrations up to 70% supported an S(N)2 mechanism of hydrolysis for the prodrug. These results suggest that an O-(imidomethyl) type prodrug is insensitive to enzymatic catalysis of hydrolysis yet may hydrolyze quickly enough to release 17β-estradiol faster than 17β-estradiol is conjugated and excreted.
- Patel,Prankerd,Sloan
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p. 1477 - 1481
(2007/10/02)
-
- Mechanism of Hydrolysis of O-Imidomethyl Derivatives of Phenols
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Three series of O-imidomethyl derivatives of para-substituted phenolic compounds were synthesized and their rates of hydrolysis were studied.Saccharin, phthalimide, and succinimide served as the imide portions of the derivatives.Their rates of hydrolysis were found to be first order with respect to hydroxide from pH 7.0 to 10 or 11 and dependent on the acidity (leaving group potential) of both the imide and the phenol portions.The more acidic the imide or the phenol, the faster the rate of hydrolysis.However, the rates of hydrolysis were more sensitive to the acidity of the phenol.Trapping experiments with cyanide also suggested that the phenol anion was functioning as the leaving group in what is apparently an SN2 reaction.An amide derivative was found to hydrolyze more slowly than predicted from the analogous series and the pKa of the amide.This result is apparently due partially stereoelectronic constraints in the imide series that cause the CH2-O bond to be oriented more nearly perpendicular to the plane of the C(=O)N group and hence more accessible to nucleophilic attack.
- Getz, John J.,Prankerd, Richard J.,Sloan, Kenneth B.
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p. 4913 - 4918
(2007/10/02)
-
- Retro-ene Reaction I: Reaction of N-Hydroxymethylsaccharin with Benzoyl Chlorides and Alkyl Halides
-
N-Benzoylsaccharins, N-(saccharinylmethyl) benzoates and N-alkylsaccharins were synthesized from N-hydroxymethylsaccharin and the corresponding benzoyl chlorides or alkyl halides under different conditions.The reaction mechanisms are also discussed.
- Kim, Sung-Kyu,Moon, Jung-Gyen,Lee, Sang-Gyeong,Choi, Sam-Young,Cho, Su-Dong,et al.
-
p. 353 - 356
(2007/10/02)
-
- Encapsulation composition for use with chewing gum and edible products
-
The present invention is method and composition for protecting an active ingredient and providing controlled release therefor, especially in a chewing gum composition, which includes a high molecular weight polyvinyl acetate blended with a hydrophobic plasticizer which forms a film with the high molecular weight polyvinyl acetate in the absence of an added solvent therefor. The active ingredient, such as the artificial sweetener aspartame, is blended into the encapsulating composition as, for example, by melt blend which can then be cooled to a solid and ground into particulate. The encapsulated active ingredient can then be used in a composition for ingestion by a human in the form of, for example, a chewing gum with extended shelf life and highly controlled release of the active ingredient.
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- Metal-assisted reactions. Part 20. Catalytic transfer hydrogenolysis of phenolic C-O bonds
-
After conversion of phenols into O-pseudosaccharyl ethers (2) catalytic transfer hydrogenolysis with Pd/C catalyst and sodium phosphinate as hydrogen donor gave arenes (ArH) in good yield. As an example of the application of this reaction in synthesis, oestrone was onverted into oestratrienone in a high yielding, one step reaction.
- Brigas,Johnstone
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p. 5789 - 5790
(2007/10/02)
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- Synthesis of -yl>ketene S,S-Acetals and Their Reaction with Hydrazine Hydrate
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The previously unknown ketene S,S-acetals 2, 3, and 4 are prepared by dithiocarboxylation reaction of methylene-active saccharin derivatives 1 in the presence of sodium hydride/carbon disulfide in dry DMF followed by alkylation.Compounds 2a, 3a, and 4a are treated with hydrazine hydrates (85percent) to give 2-hydrazono-3,3-bis(methylthio)propiophenone (6a) and methyl or ethyl pyruvate 6b or 6c, respectively.
- Doelling, Wolfgang,Herrmann, Cornelia,Augustin, Manfred
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p. 927 - 929
(2007/10/02)
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- Kinetics and Mechanism of Oxidation of Propiophenone and Butyrophenone by N-Bromosaccharin in Aqueous Acetic Acid Medium
-
The title reaction has been studied in aqueous acetic acid medium in presence of Hg(OAc)2.Order with respect to substrate, oxidant and +> is one in each.Added saccharin retards the rate of reaction.The reaction system did not induce polymerisation of added acrylonitrile indicating the absence of free radicals in the system.Thermodynamic parameters have been evaluated.The order of reactivity among the two substrates studied is propiophenone > butyrophenone.A suitable mechanism consistent with the observed results is proposed.
- Mohan, K. Vijaya,Rao, P. Raghunath,Sundaram, E. V.
-
-
- REACTION OF N-HALOGENOIMIDES WITH SULFUR. THIODIIMIDES
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The reaction of N-halogenoimides with sulfur leads to the production of thiodiimides.The latter are active sulfur-transferring reagents.
- Borovikova, G.S.,Levchenko, E.S.,Kaminskaya, E.I.
-
-
- The Reaction of Saccharin Derivatives with N,N-Diethylprop-1-ynamine: Formation of Cyclobutenyl Saccharinates and of a Spiro-oxete
-
Saccharin and two equivalents of N,N-diethylprop-1-ynamine give a cyclobutenyl saccharinate (4) which, on bromination, gives the N-(cyclobutenyl cation)saccharin derivative (8), whose structure was established by X-ray crystallography ; N-methylsaccharin reacts with one equivalent of ynamine to yield the spiro-oxete (9): this represents the second isolation of such a stable oxete from reaction of an ynamine with a carbonyl group.
- Abramovitch, Rudolph A.,Ooi, Gino H. C.,Sun, Han-Li,Pierrot, Marcel,Baldy, Andre,Estienne, Jacques
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p. 1583 - 1584
(2007/10/02)
-
- Preparation of saccharin
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A process for the preparation of saccharin by reacting an aqueous hydrochloric acid solution of o-methoxycarbonylbenzenediazonium chloride with sulfur dioxide, wherein (a) the aqueous diazonium salt solution is reacted with sulfur dioxide at from 0° to 100° C. in the presence of a water-immiscible or only partially water-miscible inert organic solvent, (b) in order to decompose the diazonium salt, the reaction mixture is treated simultaneously or subsequently with a diazonium salt decomposition catalyst, (c) the aqueous organic reaction mixture, or the organic phase obtained after removing the aqueous phase, is treated with an oxidizing agent at from 0° to 100° C. and (d) the organic phase is reacted with aqueous ammonia at from 0° to 50° C. and the saccharin is isolated from the aqueous phase in a conventional manner by acidifying with a strong acid.
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- Process for producing chlorosulfonylbenzoylchloride
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Chlorosulfonylbenzoylchloride having the formula STR1 wherein X is hydrogen, halogen or nitro is prepared by reacting phosgene with an aromatic sulfocarboxylic acid having the formula STR2 or an alkali metal salt or alkaline earth metal salt thereof in the presence of dimethylformamide.
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- Process for producing saccharin
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An o-sulfobenzimide having the formula: STR1 is prepared by reacting phosgene with a methylbenzoate-o-sulfonate having the formula: STR2 WHEREIN M represents potassium or calcium, n is 1 when M is K and n is 2 when M is Ca, in an inert organic solvent in the presence of dimethylformamide; and then reacting ammonia with the reaction product.
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- Pyrolysis of 2-sulfochloride benzoates
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Ortho-sulfobenzoic anhydride is synthesized by pyrolysis of the 2-sulfochloride benzoates. The benzoate intermediates are readily prepared by reacting either the esters of dithiodibenzoic acid with chloride water or the 2-diazonium chloride benzoates with sulfur dioxide. The invention also provides for the total synthesis of saccharin, free of bitter tasting contaminants, from such reactants, the ultimate step in such synthesis being the ammonolysis of the o-sulfobenzoic anhydride.
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