- AEROBIC OXIDATIVE SYNTHESIS OF SULFONAMIDE USING Cu CATALYST
-
The present invention relates to a method for oxidative synthesis of sulfonamides using copper catalysts. , Oxygen (O) is used. 2 The oxidative synthesis of sulfonamides (1) comprises reacting a 2 th or sulfonyl hydrazide primary amine with a sulfonyl hydrazide (sulfonamide) with a copper catalyst on a solvent under the conditions in which the sulphonamide is fed. The oxidation coupling of the present invention showed extensive substrate ranges in an amine comprising a 2 primary amine, 1 primary amine and amine hydrochloride salt. It is worth notable that non-reactive aliphatic sulfonyl hydrazides in previously reported anaerobic systems can be used for the aerobic oxidation coupling of the present invention. The oxidation coupling of the present invention has been more effective on large scale.
- -
-
Paragraph 0033-0037; 0039-0054; 0066-0069; 0175-0176
(2021/04/06)
-
- Imidazotetrazines as Weighable Diazomethane Surrogates for Esterifications and Cyclopropanations
-
Diazomethane is one of the most versatile reagents in organic synthesis, but its utility is limited by its hazardous nature. Although alternative methods exist to perform the unique chemistry of diazomethane, these suffer from diminished reactivity and/or correspondingly harsher conditions. Herein, we describe the repurposing of imidazotetrazines (such as temozolomide, TMZ, the standard of care for glioblastoma) for use as synthetic precursors of alkyl diazonium reagents. TMZ was employed to conduct esterifications and metal-catalyzed cyclopropanations, and results show that methyl ester formation from a wide variety of substrates is especially efficient and operationally simple. TMZ is a commercially available solid that is non-explosive and non-toxic, and should find broad utility as a replacement for diazomethane.
- Svec, Riley L.,Hergenrother, Paul J.
-
supporting information
p. 1857 - 1862
(2019/12/27)
-
- Synthesis and evaluation of novel S-benzyl- and S-alkylphthalimide- oxadiazole -benzenesulfonamide hybrids as inhibitors of dengue virus protease
-
Direct acting antiviral drugs (DAADs) are becoming therapeutics of choice for the treatment of viral infections. Successful development of anti HIV and HCV drugs by targeting the viral proteases has provided impetus for discovering newer DAADs. Dengue virus (DENV) protease, which is composed of two nonstructural proteins, NS2B and NS3pro, can be likewise exploited for discovering new anti-dengue therapeutics. In this study, we have linked together two pharmaceutically interesting motifs, namely 1,3,4-oxadiazole and benzenesulfonamide in two alternative series to develop novel S-benzylated and S-alkylphthalimidated hybrids. For the first series of hybrids, 4-aminobenzoic acid (1) was reacted with substituted benzenesulfonyl chlorides via its amino group, whereas the carboxylic acid side was elaborated to sulfonamido-1,3,4-oxadiazole-2-thiols (6a/b) in three steps. At this stage, the intermediates 6a/b were bifurcated to either S-alkylphthalimidated (8a-j) or S-benzylated (9a-c) hybrids by reacting with corresponding halides. For the alternative series of hybrids, the carboxylic acid group of probenecid (10) was similarly elaborated to sulfonamido-1,3,4-oxadiazole-2-thiols (13), and diverged to S-alkylphthalimidated (14a-f) and S-benzylated hybrids (15a-e). Bioactivity assays demonstrated that 8g and 8h are the most potent inhibitors among the synthesized analogs, exhibiting the IC50 values of 13.9 μM and 15.1 μM, respectively. Computational assessment predicted the binding of the inhibitors at an allosteric site developed in the open conformation of DENV2 NS2B/NS3pro. Taken together these findings point out that the synthesized hybrid inhibitors possess a great potential for further antiviral drug development.
- Batool, Farwa,Hamdani, Syeda Shamila,Hameed, Shahid,Khan, Bilal Ahmad,Mughal, Ehsan Ullah,Saeed, Muhammad,Saleem, Hafiza Nosheen
-
-
- Cu-catalyzed aerobic oxidative synthesis of sulfonamides from sulfonyl hydrazides and amines
-
An environmentally friendly route for sulfonamides has been developed. The oxidative coupling of sulfonyl hydrazides and amines was catalyzed by CuBr2 to produce various sulfonamides with the water and nitrogen gas as byproducts. Preliminary experiments revealed that the sulfonyl radical is likely to be involved in the reaction mechanism.
- Chung, Sohyun,Kim, Jinho
-
supporting information
p. 792 - 795
(2019/02/16)
-
- Mild Esterification of Carboxylic Acids via Continuous Flow Diazotization of Amines
-
A new continuous flow protocol for the diazotization of methylamine with 1,3-propanedinitrite in THF is reported. The synthesis of methyl esters was achieved in high yields from a variety of carboxylic acids in 20 min at 90 °C. Additionally, this protocol was extended to other aryl and alkyl amines, namely secondary amines, to produce various substituted esters in high yield using 2-MeTHF as a solvent. The reaction conditions were compatible with many functional groups, namely nitrogen-containing heterocycles, alkynes, alkenes, alcohols, and phenols. Mechanistic investigations reveal that the reaction appears to proceed through a transient diazonium species rather than a diazo intermediate.
- Audubert, Clément,Lebel, Hélène
-
supporting information
p. 4407 - 4410
(2017/08/23)
-
- Prodrugs and mutual prodrugs: Synthesis of some new pyrazolone and oxadiazole analogues of a few non-steroidal anti-inflammatory drugs
-
Naproxen, probenecid, diclofenac, ibuprofen and indomethacin were converted to hydrazide derivatives via their methyl ester by reacting with hydrazine hydrate, which were further condensed with β-keto esters to get the pyrazolone derivatives. The hydrazide derivatives of probenecid and diclofenac were also reacted with biphenyl acetic acid while naproxen hydrazide was reacted with p-chloro benzoic acid besides biphenyl acetic acid to synthesize their oxadiazole analogues. Some selected members of the compounds prepared were screened for their anti-inflammatory and analgesic activity.
- Sharma, Vibha,Khan
-
-