Current organic synthesis最新文献

A series of dispersed reactive dyes bearing azo and cyanuric groups were synthesized, and their structures were established using spectral and elemental analyses.

Method: The IR, 1H NMR, and DFT studies indicated that the prepared reactive disperse dyes predominately exist as hydrazone tautomers. The electronic absorption spectra in methanol were observed and compared to those computed using B3LYP/6-311G(d,p). The dyeing efficiency of the produced dispersed reactive dyes was examined on polyester, cotton, and polyester/cotton blended fabrics.

Results: The degree of exhaustion and the quick properties of the dyed samples in terms of perspiration, washing, scorch and light fastness were assessed. It was found that reactive disperse dyes under investigation have a higher affinity for dyeing polyester textiles than cotton textiles.

Conclusion: Moreover, the reflectance and color strength of the synthesized dyes were measured and discussed.

The synthesis of coumarin derivatives has been an essential topic since its discovery in 1820. In bioactive compounds, the coumarin moiety serves as a backbone, as many such bioactive compounds with the coumarin moiety play a significant role in their bioactivities. Given this moiety's relevance, several researchers are developing fused-coumarin derivatives to create new drugs. Mostly the approach done for this purpose was a multicomponent reaction based. Over the years, the multicomponent reaction has gained enormous popularity, and this approach has evolved as a replacement for conventional synthetic methods. Because of all these perspectives, we have reported the various fused-coumarin derivatives synthesized using multicomponent reactions in recent years.

Background: Multi-component reactions for the preparation of pyrazolophthalazine derivatives under microwave irradiation from different aromatic aldehydes with a mixture malononitrile and phthalhydrazide derivatives were established. The antimicrobial activity of the target compounds was evaluated against four bacteria and two fungi using standard antibiotics Ampicillin and mycostatine as reference drugs. The structure-activity relationship studies reported that the substitution at 2,4, and 2,5-positions in the 1H-pyrazolo nucleus with the specific halogen atom increases the ability of the molecule against the antimicrobial activity. The structures of the synthesized compounds were established based on spectral data, IR, 1H NMR, 13C NMR and MS data.

Objectives: Design a series of new pyrazolophthalazine moieties and study the antimicrobial activity of these compounds Materials and Methods: pyrazolophthalazine derivatives 4a-j were synthesized by reaction of phthalhydrazide (1) with malononitrile (2), and various halogen aromatic aldehydes 3a-j in and EtOH/ Pip. Solution under microwave irradiation settings for two minutes at 140 °C Results: In this study, the antimicrobial activity of the synthesized compounds 4a-j was examined for their in vitro antimicrobial activity by using the agar diffusion method using Mueller-Hinton agar medium for bacteria and Sabouraud's agar medium for fungi. Ampicillin and mycostatine were included in the experiments as reference drugs.

Conclusion: A series of new pyrazolophthalazine derivatives were synthesized in this work. All compounds were evaluated for antimicrobial activity.

Introduction: L-proline is an efficient chiral small-molecule organocatalyst for the direct asymmetric aldol reaction between unmodified acetone and a variety of aldehydes.

Method: However, it is difficult to separate from the reaction medium for reuse. In this work, polyacrylic acid (PAA) supported The acylation reaction between L-hydroxyproline and PAA prepared l-proline (P(AA-co-PA)) catalysts with various catalyst loadings. Fourier characterized them transforms infrared spectroscopy, nuclear magnetic resonance spectrum, gel permeation chromatography and thermogravimetry analysis.

Result: These macromolecular catalysts were used to catalyze acetone and benzaldehydes' direct asymmetric aldol reaction. The influence of the catalyst structure on the catalytic performance was studied, and the reaction conditions were optimized.

Conclusion: The results showed that P(AA-co-PA) with 50 mol% catalyst loading had excellent catalytic performance, much higher than that of L-proline and L-hydroxyproline. Its recovery was achieved by simple filtration. After being reused 7 times, its catalytic performance was still higher than that of L-proline.

Aim: Organic electro-optic (EO) materials have recently gained considerable attention owing to their advantages compared to inorganic EO materials. Among different kinds of organic EO materials, organic EO molecular glass exhibits desired prospect because of its high chromophore loading density and large macroscopic EO activity.

Introduction: The objective of this study is to design and synthesize a novel organic EO molecular glass JMG utilizing julolidine moiety as the electron donor, thiophene moiety as the conjugated bridge, trifluoromethyl substituted tricyanofuran derivate (Ph-CF3-TCF) as the electron acceptor.

Method: The JMG's structure was characterized through NMR and HRMS. The photophysical property, glass transition temperature, first hyperpolarizability (β) and dipole moment (μ) of JMG were determined through UV-vis spectra, DSC test and DFT calculation.

Results: JMG's Tg reached to 79 °C and it can form high-quality optical film. The theoretical calculation shows that the first hyperpolarizability (β) and dipole moment (μ) of JMG were calculated to 730×10-30 esu and 21.898 D. After connecting poling with the poling voltage of 49 V/μm at 90 ℃for 10 min, the highest EO coefficient (r33) of the poled JMG films reached to 147 pm/V.

Conclusion: A novel julolidine-based NLO chromophore with two tert-butyldiphenylsilyl (TBDPS) groups was successfully prepared and characterized. TBDPS group is introduced as the film-forming group, and it also plays the role of isolation group, which can suppress the electrostatic interaction between chromophores, improve the poling efficiency and further enhance the EO activity. The excellent performances endow JMG with potential applications in device fabrication.

Introduction: Seven new psoralen derivatives were synthesised by carbodiimide coupling to active carboxylic acid to amide formation in mild reaction conditions.

Methods: The psoralen derivatives were produced through the condensation of seven different types of amine groups consisting of electron withdrawing groups and electron donating groups.

Results: All the synthesised compounds were obtained with moderate to high yields. Structural characterization using ATR-FTIR, 1H NMR, 13C NMR, and HRMS has confirmed their structure. Moreover, in silico evaluation of the psoralen derivatives against the AChE enzyme was performed, and acetylcholinesterase inhibitory activity of psoralen derivatives was also conducted.

Conclusion: Results from molecular docking show the potential of compound 12e as AChE inhibitors due to its highest binding energy value. It was further supported by the anti-acetylcholinesterase activity of compound 12e, which has 91.69% inhibition, comparable to galantamine (94.12%). Furthermore, 100 ns run molecular dynamics (MD) simulation was used to refine docking results.

Background: Downy mildew is one of the major fungi causing significant economic losses to crops. The resistance of this fungus to current fungicides is increasing and new fungicides with a unique mode of action are needed.

Objective: To find a novel pyrazole amide derivative as a potential fungicide.

Methods: A series of pyrazole-5-carboxamide derivatives containing a diaryl ether were designed and synthesized by the Intermediate derivatization method (IDM). Their fungicidal activities against Pseudoperonospora cubensis (P. cubensis, cucumber downy mildew) were evaluated in the greenhouse.

Results: Bioassays indicated that several compounds exhibited excellent fungicidal activity against P. cubensis in vivo. In particular, T24 (EC₅₀ = 0.88 mg L^-1) had the highest activity compared with Dimethomorph and Fluazinam and other analogues. The relationship between the activity and the structure of these derivatives was analyzed, and an accurate and reliable three-dimensional quantitative structure-activity relationship (3D-QSAR) model was established to determine that electrostatic and steric fields had important effects on the improvement of fungicidal activity.

Conclusion: The novel pyrazole-5-carboxamide derivative T24 can be considered a potential fungicide for P. cubensis control.