182277-06-1Relevant academic research and scientific papers
Asymmetric syntheses of piperidino-benzodiazepines through 'cation-pool' host/guest supramolecular approach and their DNA-binding studies
Markandeya, Nagula,Shankaraiah, Nagula,Reddy, Ch. Sanjeeva,Santos, Leonardo Silva,Kamal, Ahmed
experimental part, p. 2625 - 2630 (2011/02/16)
The asymmetric synthetic approach to piperidino-benzodiazepine 4a (a homolog of DC-81) has been developed. The absolute stereochemistry of 4 and 5 has been assigned to be (S) at C-12a position. This procedure features the use of a 'cation-pool' strategy and also a host/guest supramolecular co-catalysis approach. In this study, the chloroformate of 8-phenylmenthyl has been employed as a chiral auxiliary and includes one-pot conditions for anodic oxidation, which are followed by nucleophilic addition to an N-acyliminium ion. In addition, intramolecular azido reductive-cyclization and nitro reductive dithioacetal deprotective tandem-cyclization approaches have also been utilized for the syntheses of these compounds 4a,b and 5a,b. Some of the representative compounds exhibited an enhanced DNA-binding ability in comparison to the natural product DC-81.
Synthesis of pyrrolo[2,1-c][1,4]benzodiazepine antibiotics: Oxidation of cyclic secondary amine with TPAP
Kamal, Ahmed,Howard, Philip W.,Reddy, B.S. Narayan,Reddy, B.S. Praveen,Thurston, David E.
, p. 3223 - 3230 (2007/10/03)
A facile procedure for the preparation of the imine form of the pyrrolo(2,1-c][1,4]-benzodiazepine ring system by the oxidation of eyelid secondary amine with catalytic amounts of tetra-n-propylammonium perruthenate (TPAP) and N-methylmorpholine N-oxide (NMO) as a co-oxidant is described. This oxidative method is devoid of side-products and is thus a significant improvement over the Swern oxidation previously reported.
An efficient synthesis of pyrrolo[2,1-c][1,4]benzodiazepine antibiotics via reductive cyclization
Kamal, Ahmed,Reddy, B. S. Nararyan,Reddy, B. S. Praveen
, p. 1825 - 1828 (2007/10/03)
A new and convenient one-pot synthesis of pyrrolo[2,1-c][1,4]benzodiazepine (PBD) ring system has been achieved by a reductive cyclization employing N,N-dimethylhydrazine and FeCl3.6H2O in good yields.
A new facile procedure for the preparation of pyrrolo[2,1-c][1,4]benzodiazepines : Synthesis of the antibiotic DC-81 and its thio analogue
Kamal, Ahmed,Reddy, B. S. Praveen,Reddy, B. S. Narayan
, p. 2281 - 2284 (2007/10/03)
An efficient synthesis of the imine form of the pyrrolo[2,1-c][1,4] benzodiazepine ring system based on a new reductive cyclization procedure is described. The naturally occuring antibiotic DC-81(5c) and its 5-thio analogue (7c) have also been synthesized to illustrate the usefulness of this methodology.
A new route for the synthesis of pyrrolo[2,1-c][1,4]benzodiazepine antibiotics via oxidation of cycle secondary amine
Kamal,Rao
, p. 385 - 386 (2007/10/03)
The synthesis of the imine-containing pyrrolo[2,1-c][1,4]benzodiazepine DNA-binding antitumour antibiotics was achieved by a new method of oxidation of cyclic secondary amines which does not endanger the stereochemical integrity of the C-11a position.
New approaches to pyrrolo[2,1-c][1,4]benzodiazepines: Synthesis, DNA-binding and cytotoxicity of DC-81
Bose, D. Subhas,Jones, Gary B.,Thurston, David E.
, p. 751 - 758 (2007/10/02)
Two routes to the naturally occuring DNA-binding antitumor antibiotic DC-81 are described, one of which involves a novel cyclization process based on acid resin. The second route involves the synthesis of a new compound, 6-nitrovanillic acid, a key A-ring component of many naturally occuring PBDs. These routes have provided a sufficient quantity of DC-81 to allow complete characterization and evaluation in DNA-binding and in vitro cytoxicity studies.
