Volume 22, Issue 4

The Chloranthaceae is a small family with only four genera ( Ascarina, Chloranthus, Hedyosmum, Sarcandra ), of which nearly 70 species are distributed around the world. Chemical constituents in Chloranthaceae plants, especially sesquiterpenes, have attracted a great deal of attention in recent 5 years. Many characteristic constituents of this family may be responsible for anti-microbial, anti-tumor and other activities. In order to provide information for the future research, the structures and biological activities of the known constituents from the plants of Chloranthaceae have been reviewed in this article.

( E )-3-(3-Aryl-1-phenyl-1 H -pyrazol-4-yl)-1-(pyridin-3-yl)prop-2-en-1-ones 4a–i have been synthesized and evaluated for their in vitro cytotoxicity against a panel of three human cancer cell lines Caco-2, MIA PaCa-2, MCF-7 and a normal NIH-3T3 cell line. Compound 4g is cytotoxic with the IC 50 value of 15.32±0.62 μ m against the Caco-2 cell line.

The reaction of 2-aryl-4-phenyl-5,6,7,8-tetrahydro-4 H -selenochromenes 1–3 with trifluoroacetic acid and triethylsilane furnished a novel class of compounds, 2-aryl-4-phenyloctahydroselenochromenes.

Carbothioamides 4a , b , obtained from nalidixic acid, were converted to the corresponding 1,3-thiazolidine derivatives 5a,b by cyclocondensation with 2-bromo-1-(4-chlorophenyl)ethanone. Treatment of 4a,b with base afforded 1,2,4-triazoles 6a,b . The synthesis of 1,3-oxazolidine 7 was performed by the reaction of compound 4a with ethyl bromoacetate. Treatment of 4a with acid produced 1,3,4-thiadiazole 8 . The reaction of compounds 6a and 6b with several heterocyclic amines in the presence of formaldehyde gave the corresponding Mannich bases 9–15 containing various pharmacophore groups. Conventional and microwave-assisted methods were used for the synthesis. The effect of an acid catalyst on Mannich reactions was investigated. The structures of the newly synthesized compounds were elucidated on the basis of 1 H NMR, 13 C NMR, FTIR, EIMS techniques, and elemental analysis. All compounds were screened for their antimicrobial activity.

Readily prepared copper nanoparticles are an effective catalyst for 1,3-dipolar cycloaddition of carbohydrate azide and a variety of alkynes that furnishes the corresponding 1,2,3-triazole-sucrose derivatives in excellent yields. Products were screened for their antimycobacterial activity against Mycobacterium tuberculosis H37Rv strain. Two compounds, 3b , c , demonstrate significant growth inhibitory activity against the bacterial strain with a MIC of 3.125 mg/mL. The presence of an amide group on the 1,2,3-triazole ring enhances the inhibition activity of the molecules. The active compounds are not toxic to a normal cell line which signifies the lack of general cellular toxicity of these compounds.

A clean and environmentally benign route for the preparation of substituted thiazoles 4a–k via a three component reaction of an aldehyde, thiosemicarbazide and a bromoacetophenone in the presence of 3,3′-(pentane-1,5-diyl)bis(1,2-dimethyl-1 H -imidazol-3-ium) bromide is reported. The present methodology offers several advantages such as solvent-free conditions, excellent yields, simple procedure, mild conditions and reduced environmental consequences. The ionic liquid can be recovered and reused. All synthesized compounds were characterized by IR, NMR and elemental analysis.

A series of dihydrochromeno[4,3- b ]pyrazolo[4,3- e ]pyridines has been synthesized using a simple and efficient one-pot, three-component procedure. The products were obtained in good yields in the presence of heterogeneous nanoporous acid catalyst (SBA-Pr-SO 3 H).