Synthesis of a proline-rich cyclic hexapeptide - diandrine A [VI] was accomplished by coupling of tetrapeptide unit Boc-Gly-Pro-Trp-Pro-OH with dipeptide unit Tyr-Phe-OMe followed by cyclization of linear peptide unit [V] under alkaline condition. Structure of newly synthesized cyclopolypeptide was elucidated by means of spectral techniques including FTIR, 'H NMR, "C NMR, MS analyses. VI was su...

A series of novel pyrazoline derivatives 5-(substituted aryl)-3-(3,4-dimethoxyphenyl)-1-(2,4dinitrophenyl)-4,5-dihydro-1H-pyrazole (5a-l) were synthesized by heating 2,4-dinitrophenyl hydrazine (4) with (E)-3-(3,4-dimethoxyphenyl)-1-substituted aryl prop-2-en-1-one (3) in presence of catalytic amount of concentrated H2SO4. The structures of the novel derivatives were confirmed by various spectr...

New drugs active against drug-resistant tuberculosis are urgently needed to extend the range of TB treatment options to cover drug resistant infections. Quinoxaline derivatives show very interesting biological properties (antibacterial, antiviral, anticancer, antifungal, antihelmintic, insecticidal) and evaluation of their medicinal chemistry is still in progress. In this review we report the p...

  A new bioactive proline-rich cyclohexapeptide - diandrine C (6), previously isolated from whole plant of Drymaria diandra (Caryophyllaceae), was synthesized through coupling reactions of tetrapeptide unit Boc-Gly-l-Pro-l-Tyr-l-Trp-OH with dipeptide unit l-Pro-Gly-OMe using N,N-diisopropylcarbodiimide (DIPC) as the coupling agent, followed by cyclization of l...

Acaciaside A and B, two acylated triterpenoid bisglycosides isolated from the funicles of Acacia auriculiformis, are known to have antihelmintic activity. Since the saponins contain a conjugated unsaturated system that is highly susceptible to peroxidation, we investigated the interaction of saponins and membrane using rat liver microsomes as our model. Microsomal membranes were incubated with ...

  A new bioactive proline-rich cyclohexapeptide - diandrine C (6), previously isolated from whole plant of Drymaria diandra (Caryophyllaceae), was synthesized through coupling reactions of tetrapeptide unit Boc-Gly-l-Pro-l-Tyr-l-Trp-OH with dipeptide unit l-Pro-Gly-OMe using N,N-diisopropylcarbodiimide (DIPC) as the coupling agent, followed by cyclization of l...

Emergence of resistance by bacterial and fungal stains towards existing antimicrobial agents is one of the major problem as well as motivation to synthesize a new class of antimicrobial agents possessing potent activity compared to commonly used therapy. Coumarin is the heterocyclic compound formed from benzene and pyrone ring containing oxygen and its derivatives are of wide awareness because ...

Momordica charantia L. belongs to the family Curcubitaceae and it is very common in many Brazilian regions. The plant is a liana with flowers and yellow fruits that present red seeds when are ripe. Popularly known as "melão-de-sãocaetano", "melão amargo" or "cabaço-amargo", it possesses many uses: antidiabetic, antihelmintic, antmicrobial, anticancerigenous and antioxidant. The phytochemical pr...