Organic Communications Articles

Computational investigations of fused thiophenes including not only thienothiophene, ditihieno­thiophene and thienoacene but also other thiophene-fused (hetero)-aromatic rings have been surveyed. The effect of the methods and basis sets applied on promising optoelectronic materials were elaborated. This brief review suggests the best method for the fused thiophenes to be B3LYP functional. ©2016 ACG Publications. All rights reserved.

The capacity of simple coconut water, which contains natural peroxidases, to act as a biocatalyst for the oxidative coupling-cyclization of p-(OH)-phenylpropanoids, was evaluated in this work. As a result, dimeric forms of isoeugenol (licarin A) and methyl p-coumarate (methyl dehydrodicoumarate) were obtained. The products of the reactions were characterized by optical rotatory dispersion, and 1H-NMR and 13C-NMR spectroscopy. The oxidative coupling-cyclization mechanism for coniferyl alcohol is proposed.

The cobalt(II) complex of the Halterman porphyrin, 5,10,15,20-tetrakis[(1S,4R,5R,8S)-1,2,3,4,5,6,7,8-octahydro-1,4:5,8-dimethanoanthracene-9-yl]porphyrinato cobalt(II) [Co(por*)], was synthesized and its structure was identified by X-ray analysis. Up to 80:20 trans:cis diastereomeric ratio and 82% ee were achieved in the cyclopropanation of styrene with ethyl diazoacetate by using this cobalt(II) porphyrin complex as catalyst.

The 1,1'-(5,5'-(1,3-phenylene)bis(3-aryl-4,5-dihydro-1H-pyrazole-5,1-diyl))di-ethanone (5a-e) and 1,3-bis(1-phenyl-3-(aryl)-4,5-dihydro-1H-pyrazol-5-yl)benzene (6a-e) were synthesized by addition of hydrazine hydrate and/or phenylhydrazine to 1,3-phenylene-bis-chalcone derivatives (3a-e), respectively. The structures of obtained compounds (5a-e and 6a-e) were characterized using the spectroscopic methods (NMR, IR) and elemental analysis. Addition, the in vitroantibacterial activities of compounds (5a-e) was tested against the five human pathogenic bacteria. Gentamycin and Fluconazole were used as positive control. The results were given as inhibition zone (mm) and the compounds 5d and 5e showed the same activity with standard (Fluconazole) against C. albinas.

This synthetic work reports a concise, asymmetric synthesis of b -amino- g -butyrolactone acetic acid – D-leucine hybrid 1 which will serve as model starting template sub-unit for preparing a/g foldameric oligopeptides containing unnatural g -amino acid residues. The synthesis of cis-substituted 1 was successfully achieved in six linear steps with very good stereoinduction.

An eco-friendly simple and efficient synthesis of 3,3’-bis(indolyl)methanes was carried out by electrophilic substitution reaction of indole with structurally divergent aldehydes by using succinic acid as green catalyst and water as green solvent under microwave irradiation. The advantages of this protocol are excellent yields, higher availability, inexpensive catalyst, lack of toxicity, shorter reaction time and more environmentally friendly catalyst. The reaction is chemoselective applicable only to aldehydes.

Glutamate is the major excitatory neurotransmitter in the brain. 2-Chloro-4-[2,5-dimethyl-1-(4-trifluoromethoxyphenyl)-1H-imidazol-4-ylethynyl]pyridine (5) (CTEP) is the first reported negative allosteric modulator of the metabotropic glutamate receptor 5 (mGlu5NAM) with a biological half-life of 48 hours in rodents and therefore considered an ideal tool for chronic studies in rats and mice. In this work an optimized protocol for the synthesis and purification of CTEP is reported. Through the developed new work up scrupulously described in detail, CTEP was obtained in 63 % yield, with a significant improvement in comparison with the methods reported in literature (27%) and in a tripled overall yield (27% versus 9%). Furthermore, all the intermediates between which the unreported multifunctional and appealing compound 8 as well as the final compound 5 were isolated, purified and fully characterized by IR, NMR ( 1H NMR and 13C NMR), melting point, except for the oily 7, and Elemental analysis.

Naphthoquinones have been reported to possess a variety of pharmacological properties including antibacterial, antifungal, antiviral, anti-inflammatory, anti-artherosclerotic and anticancer effects. We have successfully synthesized a series of novel naphthoquinone acylhydrazides. The straightforward synthesis of these molecules involves a coupling reaction between 2,3-dichloro-1,4-naphthoquinone and several alkyl and aromatic hydrazides and the hydrazides of the pyrimidine nucleobases, uracil and thymine. The product hydrazides were isolated in good yields and completely characterized by spectroscopic analysis. Biological evaluation against human colon cancer HCT116 cells and human breast cancer MCF-7 cells indicated that the novel hydrazides possessed significant anticancer activity.

The paper describes a new pathway for the syntheses of three natural bioactive benzofuran type compounds, namely, hostmaniene, 5-formyl-2-(isopropyl-1’-ol)benzofuran and anadendroic acid. The key synthetic strategy involved prenylation of the carboxy-phenol 7 and followed by the [5-exo-tet]cyclization reaction to furnish the benzofuran ring synthon. Subsequently, performing sequences of reactions of epoxide ring opening, ester reduction and re-oxidation of the alcohol from the benzofuran ring synthon gave all the title compounds in reasonable yield. Their structures were confirmed by both spectroscopic data and chemical transformations.