Samarendra N. Maiti

Facile conversion of azides to amines

Les azides sont reduits en amines primaires par reaction avec le chlorure stanneux dans le methanol

Reductive Cleavage of Symmetrical Disulfides with Hydrazines

Abstract An efficient method for the reductive cleavage of symmetrical disulfides with hydrazines is described.

Alkaline Earth Metal Mediated Reduction of Azides to Amines

Abstract A mild and facile method for the reduction of alkyl and aryl azides to the corresponding amines using alkaline earth metals is described.

Norepinephrine reuptake inhibitors for depression, ADHD and other neuropsychiatric disorders

Neuropsychiatric disorders have been actively studied for several decades. Many of these disorders were treated by pharmacotherapy, certain forms of psychotherapy, and electroconvulsive therapy. Several classes of drugs with a range of binding selectivities have been discovered and used in the treatment of various central nervous system (CNS) disorders. The earlier drugs had undesired side effects because of their binding to a broad range of neurotransmitters. However, with the advancement of science, there is an increasing understanding of the role of monoamine neurotransmitters in various CNS disorders, which had resulted in the rational design of potent drugs with very selective binding properties. Yet, there are many unanswered questions, and the CNS research is being more actively pursued than ever with newer additional tools such as magnetic resonance imaging (MRI), molecular imaging by positron emission tomography (PET), single-photon emission tomography (SPECT), etc. The goal of this review is to bring together the recent discoveries on selective norepinephrine reuptake inhibitors, developments, and their uses in depression and ADHD. Some of the dual inhibitors of norepinephrine and serotonin transporters have also been included in this review, as these have very similar applications.

Design, synthesis, and pharmacological evaluation of phenoxy pyridyl derivatives as dual norepinephrine reuptake inhibitors and 5-HT1A partial agonists

Preclinical studies suggest that compounds with dual norepinephrine reuptake inhibitor (NRI) and 5-HT(1A) partial agonist properties may provide an important new therapeutic approach to ADHD, depression, and anxiety. Reported herein is the discovery of a novel chemical series with a favorable NRI and 5-HT(1A) partial agonist pharmacological profile as well as excellent selectivity for the norepinephrine transporter over the dopamine transporter.

Studies on penam sulfones III. Synthesis and β-lactamase inhibitory activity of sodium (6R)-6-(α-hydroxybenzyl)-2β-methoxyiminomethyl-2α-methylpenam-3α-carboxylate 1,1-dioxide and sodium 2β-acyl-2α-methylpenam-3α-carboxylate 1,1-dioxide

Abstract The synthesis and in vitro synergies of (6R)-6-(α-hydroxybenzyl)-2β-methoxyiminomethyl-2α-methylpenam-3α-carboxylate 1,1-dioxide ( 4 ) and 2β-acyl-2α-methylpenam-3α-carboxylate 1,1-dioxide ( 15 ) are described. Compound 15 showed good in vitro synergy in combination with piperacillin and ceftazidime against chromosomally mediated class I cephalosporinase producing organisms including TEM, SHV, and OXA-type enzymes producing microorganisms.

Synthesis of 7α-methoxy-2-(1,3-dithiolan-2-ylidene)cephem sulphones. A new series of human leukocyte elastase inhibitors

Abstract Treatment of 3-methyl-3-cephem sulphone with sodium hydride followed by carbon disulphide and alkyl halide provides an entry to 2-(1,3-diothiolan-2-ylidene)-cephem derivatives, which are new potent inhibitors of HSE.

A One Pot Synthesis of 1-Substituted-1,2,3,7-tetrahydro-8-nitroimidazo [1,2-a] [1,2,6] thiadiazine-7 (1H) one-5,5-dioxides

Abstract Reaction of chlorosulfonyl isocyanate with nitroketene aminals of imidazolidines afforded acyclic intermediates which on treatment with diisopropylamine were smoothly transformed into the corresponding 1-substituted-1,2,3,7-tetrahydro-8-nitroimidazo [1,2-a] [1,2,6] thiadiazine-7 (1H) one-5, 5-dioxides.

Synthesis and beta-lactamase inhibitory activity of 2,2-bis(monosubstituted) methylpenicillin sulfones

A series of 2,2-bis(monosubstituted) methylpenicillin sulfones were prepared from 6,6-dibromopenicillanate by a double sulfoxide rearrangement. β-Lactamase inhibitory activity of 2,2-bis(chloromethyl)penicillanic acid sulfone was studied and its activity was compared with YTR-830

The trapping of sulfenic acids from penicillin sulfoxides: ethyl 2-mercaptoacetate

Abstract The thermolysis of trichloroethyl 6-phenoxyacetamido penicillanate sulfoxide and ethyl 2-mercaptoacetate in toluene gave the unsym-azetidinone disulfide(β,γ-isomer) in 65% yield. With added catalytic amounts of N,N-dimethylaniline the α,β-isomer was the major product (60%), along with a new β-lactam cleaved product, 8 (5–6%).