Microwave-Assisted Synthesis and Evaluation of Antimicrobial Activity of 3-{3-(s-Aryl and s-Heteroaromatic)acryloyl}-2Hchromen-2-one Derivatives

The exploration of potential utilization of microwaves as an energy source for heterocyclic synthesis was herein investigated using condensation of 3-acetylcoumarin (1) with aromatic and heteroaromatic aldehydes to afford the corresponding aromatic chalcones (2a–j) and heteroaromatic chalcones (3a–e and 4a–e), respectively, in good to excellent yield within 1–3 min. The chemical structures were confirmed by analytical and spectral data. All the synthesized compounds were screened for their antibacterial activity and 3-{3-(4-dimethylaminophenyl)acryloyl}-2H-chromen-2-one (2i) was discovered to be the most active at minimum inhibitory concentration (MIC) value of 7.8 µg/m

Tertiary alkylamines as nucleophiles in substitution reactions at heteroaromatic halide during the synthesis of the highly potent pirinixic acid derivative 2-(4-chloro-6-(2,3-dimethylphenylamino)pyrimidin-2-ylthio)octanoic acid (YS-121)

YS-121 [2-(4-chloro-6-(2,3-dimethylphenylamino)pyrimidin-2-ylthio)octanoic acid] is the result of target-oriented structural derivatization of pirinixic acid. It is a potent dual PPARα/γ-agonist, as well as a potent dual 5-LO/mPGES-1-inhibitor. Additionally, recent studies showed an anti-inflammatory efficacy in vivo. Because of its interference with many targets, YS-121 is a promising drug candidate for the treatment of inflammatory diseases. Ongoing preclinical studies will thus necessitate huge amounts of YS-121. To cope with those requirements, we have optimized the synthesis of YS-121. Surprisingly, we isolated and characterized byproducts during the resulting from nucleophilic aromatic substitution reactions by different tertiary alkylamines at a heteroaromatic halide. These amines should actually serve as assisting bases, because of their low nucleophilicity. This astonishing fact was not described in former publications concerning that type of reaction and, therefore, might be useful for further reaction improvement in general. Furthermore, we could develop a proposal for the mechanism of that byproduct formation

Draft Genome Sequence of Rhodococcus sp. Strain ATCC 49988, a Quinoline-Degrading Bacterium.

We report here the 4.9-Mb genome sequence of a quinoline-degrading bacterium, Rhodococcus sp. strain ATCC 49988. The draft genome data will enable the identification of genes and future genetic modification to enhance traits relevant to heteroaromatic compound degradation

Process for synthesizing and formulating condensed ring polymers

Chemical process for forming low molecular weight, fully cyclized heteroaromatic prepolymers under conditions which limit chain extension or branching is described. Exact procedures used in conducting chemical reaction are defined. Advantages of process over conventional methods are presented

Entry point into new trimeric and tetrameric imide-based macrocyclic esters derived from isophthaloyl dichloride and methyl 6-aminonicotinate

The one-step reaction of isophthaloyl dichloride with the 2-aminopyridine derivative (methyl 6-aminonicotinate) yields (i) a trimer-based macrocycle (EsIO)3 and (ii) a tetramer-based macrocycle (EsIO)4 in modest isolated synthetic yields (total of 25%), together with (iii) longer open-chain oligomers. The macrocyclisation relies on the semi-flexible imide hinge formed by reaction of the 2-amino(pyridine) functional group with two acyl chloride functional groups. The determining factors in macrocycle synthesis are (a) imide formation using the heteroaromatic ortho-N functionality; (b) the inherent ability of the imide to twist by 85-115 degrees from planarity (as measured by the CO...CO imide torsion angles and from computational calculations), thereby providing a hinge for macrocyclic ring closure or potentially (non)helical assembly in oligomer/polymer formation and (c) the conformational flexibility of the isophthaloyl group with meta-related carbonyl groups to twist and adopt either syn- or anti-conformations, although the syn-conformation is observed structurally for all isophthaloyl groups in both (EsIO)3 and (EsIO)4 macrocycles

Methyl 2-(4-ferrocenylbenzamido)thiophene-3-carboxylate and ethyl 2-(4-ferrocenylbenzamido)-1,3-thiazole-4-acetate, a unique ferrocen

The conformations and hydrogen bonding in the thiophene and thiazole title compounds, [Fe(C₅H₅)(C₂₀H₁₄NO₃S)], (I), and [Fe(C₅H₅)(C₁₉H₁₇N₂O₃S)], (II), are discussed. The sequence (C₅H₄)-(C₆H₄)-(CONH)-(C₄H₂S)-(CO₂Me) of rings and moieties in (I) is close to being planar; all consecutive interplanar angles are less than 10°. An intramolecular N-H...O=Cester hydrogen bond [graph set S(6), N...O = 2.768 (2) Å and N-H...O = 134 (2)°] effects the molecular planarity, and aggregation occurs via hydrogen-bonded chains formed from intermolecular Car-H...O=Cester/amide interactions along [010], with C...O distances ranging from 3.401 (3) to 3.577 (2) Å. The thiazole system in (II) crystallizes with two molecules in the asymmetric unit; these differ in the conformation along their long molecular axes; for example, the interplanar angle between the phenylene (C₆H₄) and thiazole (C₃NS) rings is 8.1 (2)° in one molecule and 27.66 (14)° in the other. Intermolecular N-H...O=Cester hydrogen bonds [N...O = 2.972 (4) and 2.971 (3) Å], each augmented by a Cphenylene-H...O=Cester interaction [3.184 (5) and 3.395 (4) Å], form motifs with graph set R¹₂(7) and generate chains along [100]. The amide C=O groups do not participate in hydrogen bonding. Compound (II) is the first reported ferrocenyl-containing thiazole structure

Investigation of furo[2,3-h]- and pyridazino[3,4-f]cinnolin-3-ol scaffolds as substrates for the development of novel HIV-1 integrase inhibitors

With the aim to develop novel HIV-1 integrase inhibitors, we obtained a set of condensed ring systems based on the furo[2,3-h]cinnolin-3(2H)-one and pyridazino[3,4-f]cinnolin-3-ol scaffolds bearing a potential chelating pharmacophore, which can be involved in the inhibition mechanism of the enzyme. Herein, we report the design, synthesis, structural investigation and preliminary biological results of these heteroaromatic systems

Methyl 2-[(ferrocenylcarbonyl)amino]thiophene-3-carboxylate

The title compound, [Fe(C₅H₅)(C₁₂H₁₀NO₃S)], was synthesized from ferrocenecarboxylic acid and methyl 2-aminothiophene-3-carboxylate in modest yield. The substituted ring system is essentially planar through the amidothienylcarboxylate moiety, η⁵-(C₅H₄)CONH(C₄H₂S)CO₂Me, with the amido unit at an angle of 3.60 (7)° to the five-atom thienyl group, which is oriented at an angle of 3.17 (7)° to the ester moiety. The primary hydrogen bond is an intramolecular N-H...O=Ccarboxylate interaction [N...O 2.727 (2) Å], and the main intermolecular hydrogen bond involves a thienyl carboxylate and the carboxylate of a symmetry-related molecule [C...O 3.443 (3) Å]

Addition of Di(trimethylsilyl) Phosphite to Schiff Bases of 2,5-Diformylfuran

A series of 2,5-Furanyl-bis-(aminomethylphosphonic Acids) has been synthesized by the addition of di(trimethylsilyl) phosphite to azomethine bond of achiral Schiff bases derved from 2,5-diformylfuran. The stereochemical aspect of this reaction has been studied and compared with the behaviour of achiral terephthalic Schiff bases in similar reaction. Whereas, addition to achiral terephthalic Schiff bases was found to be highly stereoselective, the analogous reaction with achiral 2,5-diformylfuran Schiff bases was stereoselective exclusively in the case when the substituent is benzyl.N/

Lipase catalysed kinetic resolution of racemic 1,2-diols containing a chiral quaternary center

Optically active 1,2-diols are valuable buildings blocks in organic synthesis. In the present paper, a set of racemic 1,2-diols with an ester functional group are prepared, starting from -ketoesters in a three-step procedure with moderate yields. The racemic 1,2-diols, containing a chiral quaternary center in their structure, are subjected to selective acylation in order to perform their kinetic resolution catalysed by a set of commercially available lipases. Under optimized reaction conditions, good conversions and enantioselectivities are achieved by using the lipase PSL-C from Pseudomonas cepacia in tert-butyl methyl ether. This biocatalyst could be reused up to five times without losing its properties.Ministerio de Economía y Competitividad (contract RYC-2012-10014 for G.d.G., Grants CTQ2016-76908-C2-1-P and CTQ2016-76908-C2-2-P)European FEDER FundsJunta de Andalucía (Grant 2012/FQM 10787