Design and synthesis of low molecular weight compounds with complement inhibition activity

Design, Synthesis and Anticancer Activity of New Thiazole-Tetrazole or Triazole Hybrid Glycosides Targeting CDK-2 via Structure-Based Virtual Screening

Background & Objective:

The target tetrazole glycosides were synthesized by construction of ring system by cycloaddition reaction of benzothiazole-linked nitrile derivative and sodium azide followed by N-glycosylation process and deprotection.

Methods:

The triazole glycosides were prepared by applying click approach involving dipolar cycloaddition of benzothiazole possessing alkyne functionality and different glycosyl azides. The products incorporating acyclic analogs of sugar moieties were synthesized through alkylation using acyclic oxygenated halides.

Results:

The anticancer activity was studied against human breast adenocarcinoma cells (MCF-7) and human normal Retina pigmented epithelium cells (RPE-1). High activities were revealed by three compounds with IC50 values 11.9-16.5 µM compared to doxorubicin (18.6 µM) in addition to other four derivatives with good inhibition activities.

Conclusion:

Enzyme docking investigation was performed into cyclin-dependent kinase 2 (CDK2); a potential target for cancer medication. Compounds which have possessed highest activities revealed good fitting inside the binding site of the protein molecular surface and showed minimum binding energy.

Concise Synthesis of Natural Phenylphenalenone Phytoalexins and a Regioisomer

Concise total syntheses of the natural phytoalexins 2-hydroxy-8-(4-hydroxyphenyl)phenalen-1-one (1), 2-hydroxy-8-(3,4-dihydroxyphenyl)phenalen-1-one (2), and hydroxyanigorufone (4), together with regioisomer 3 are accomplished in 11 or 12 steps. The synthetic strategy features a Friedel-Crafts acylation to construct the 1H-phenalen-1-one tricyclic core followed by a Suzuki cross-coupling to obtain the target compounds.

Synthesis of nitrogenated lignin-derived compounds and reactivity with laccases. Study of their application in mild chemoenzymatic oxidative processes

The chemical synthesis of a series of nitrogenated lignin-derived compounds, their reactivity with laccases and further application in mild oxidative processes are here disclosed.

Synthesis and antimicrobial activity of new 1-[(tetrazol-5-yl)methyl] indole derivatives, their 1,2,4-triazole thioglycosides and acyclic analogs

New 1-[(tetrazol-5-yl)methyl]indole derivatives, their acyclic nucleoside analogs and the corresponding glycoside derivatives were synthesized. Furthermore, the [)(1,2,4-triazol-3-yl)methyl])-2H-tetrazole derivative as well as the corresponding thioglucoside were prepared. The synthesized compounds were tested for their antimicrobial activity against Aspergillus Niger, Penicillium sp, Candida albican, Bacillus subtilis, Streptococcus lacti, Escherichia coli, Pseudomonas sp., and streptomyces sp. Compounds 3, 5 and 19b exhibited potent antibacterial activity and compounds 4, 5 and 10 exhibited high activities against the tested fungi compared with fusidic acid.

Metal free, "click and click-click" conjugation of ribonucleosides and 2'-OMe oligoribonucleotides on the solid phase

A fast and practical metal free conjugation of ribonucleosides and 2'-OMe 4-mer oligoribonucleotides has been accomplished by a nitrile oxide alkyne click cycloaddition reaction on the solid-phase, the methodology is suited to modification at either, or both, the 3'- or the 5'-terminus of the oligoribonucleotide substrate.

Synthesis of 5-(thiazol-5-yl)-4,5-dihydroisoxazoles from 3-chloropentane-2,4-dione

Condensation of 3-chloropentane-2,4-dione with thioamides gives 1-(thiazol-5-yl)ethanones and subsequent Wittig olefination, followed by nitrile oxide 1,3-dipolar cycloaddition to the resulting prop-1-en-2-yl moiety, delivers racemic 5-(thiazol-5-yl)-4,5-dihydroisoxazoles. When this thiazole and isoxazoline diheterocyclic scaffold has a carboethoxy substituent at C2 of the thiazole ring, aminolysis provides for effective diversification. A 50-member library of various 5-(thiazol-5-yl)-4,5-dihydroisoxazoles is reported.

9,10-seco-9,19-Cyclolanostane arabinosides from the roots of Actaea podocarpa

Seven 9,10-seco-9,19-cyclolanostane arabinosides, named podocarpasides A-G (1-7), were isolated from the roots of Actaea podocarpa DC., a species closely related to black cohosh (a well known dietary supplement). Their structures were determined with the help of spectroscopic data including extensive 2D NMR spectroscopy. The isolates were found inactive, when tested for cytotoxic, estrogenic, and antioxidant activities in cell based assays. They were also tested for anticomplement activity against the classical pathway of complement system and only podocarpaside C (3) inhibited modest complement activity with an IC50 value of 200 microM.

Podocarpaside, a Triterpenoid Possessing a New Backbone from Actaea podocarpa

Podocarpaside (1), a novel arabinoside possessing a unique triterpene skeleton was isolated from Actaea podocarpa, a closely related species to black cohosh (dietary supplement used for menopausal disorders). Podocarpaside belongs to a new class of triterpenoids, for which the name "ranunculane" is proposed. Compound 1 possesses anticomplement activity. [structure: see text].