Synthesis,antifungal activity and 3D-QSAR study of novel nopol-based 1,3,4-thiadiazole–thioether compounds

Research on Chemical Intermediates - A series of novel nopol derivatives containing 1,3,4-thiadiazole–thioether moiety were synthesized from β-pinene, which is a natural, abundant and...     

Synthesis,anti-platelet aggregation activity evaluation and structure–activity relationships of a series of novel purine derivatives

This article described how further extensive variation of the substituents on the purine scaffold of adenosine triphosphate (ATP), and the human anti-platelet aggregation activities were modified in order to find exploitation of the structure–activity relationships (SAR). A series of novel designed 6-alkylamino-2-alkylthio-9-hydroxyalkyl(carbalkoxy) purine derivatives were synthesized via a modification procedure, and the human anti-platelet aggregation activities were evaluated. The SAR of these compounds were analyzed in detail, and the results of the structural requirements of the substituents to improve potency may provide a basis for the development of potent P2Y₁₂ antagonists.     

Synthesis and herbicidal activity evaluation of novel β-carboline derivatives

Based on the original structure of harmine, several novel 1,2,3,4-tetrahydro-β-carboline, β-carboline and 1-substituted-β-carboline derivatives bearing a substituted carbohydrazide group at C-3 were designed and synthesized to investigate the structure-activity relationship of their analogues. All of the compounds were characterized by infrared (IR), proton and carbon nuclear magnetic resonance (1H-NMR, 13C-NMR), and mass spectroscopy (MS). The bioassay tests showed that N'-benzylidene-1-phenyl-β-carboline-3-carbohydrazide (C(25)H(18)N(4)O, m.w. 390.4) (c2) and N'-(4-trifluoromethyl-benzylidene)-1-phenyl-β-carboline-3-carbohydrazide (C(26)H(17)N(4)OF(3), m.w. 458) (d2) exhibited good inhibitory activity against dicotyledonous and monocotyledonous weeds, with EC(50) values of 4.83 μM and 14.25 μM, respectively.     

Synthesis,physicochemical characterization,and TD–DFT calculations of monothiocarbohydrazone derivatives

Structural Chemistry - Derivatives of thiocarbohydrazone studied so far have shown great biological activity such as antioxidant, antimicrobial, and anticancer. Most of these compounds are...     

Design,synthesis, activity evaluation and QSAR studies of novel antimalarial 1,2,3-triazolo-β-lactam derivatives

This paper describes the synthesis of some new β-lactam derivatives containing the 1,2,3-triazole moiety. All the compounds were evaluated for their in vitro antimicrobial and antimalarial activities. Moderate to excellent antimalarial activities were encountered. The results showed that compounds 5a, 5c, 5f, 5i exhibited the most potent antimalarial activity with IC₅₀ values of 0.85, < 0.97, < 0.97, 1.81 µM against chloroquine-resistant P. falciparum K1 strain. A QSAR study highlights the structure–activity relationships that correlate the observed antimalarial activities with changes in the compounds’ structural features.     

Synthesis,spectral characterization and bioactivity evaluation of novel α-aminophosphonates

A facile synthesis of novel α-aminophosphonates 5a-j was accomplished by condensation of imines (3a-j) with diethyl phosphite (4) in ethanol at 50–60°C using easily recoverable and reusable catalyst, tetramethyl guanidine (TMG) via pudovik reaction in high yields. All the title compounds were characterized by spectral and elemental analysis. They were further screened for their abilities towards in vitro antibacterial, antifungal and antioxidant activities. The compounds 5g, 5d, 5f exhibited good antibacterial and antifungal activities compared to the standard bactericide, Penicillin and fungicide, Griseofulvin, respectively. The compounds 5h, 5i, 5g, and 5c exhibited good antioxidant activity compared to the standard ascorbic acid.     

Synthesis,antiproliferative evaluation,and structure–activity relationships of novel triazole–isoindoline hybrids bearing 3,4,5-trimethoxyphenyl moiety

As an aspect of our ongoing research on developing novel antiproliferative agents, 31 new triazole–isoindoline hybrids bearing 3,4,5-trimethoxyphenyl moiety were synthesized and evaluated for their antiproliferative activity against four cancer cell lines (HepG2, HeLa, PC-3, and HCT116). Some compounds showed excellent potency, and compared to fluorouracil, the most promising compound 6s exhibited 5.8-, 4.3-, and 1.3- fold increase in activities against HeLa, HepG2, and PC-3 cell lines with IC₅₀ values of 9.7, 10.7, and 16.8 μM, respectively. Moreover, structure–activity relationship studies indicated that a much shorter amide linkage and electron-withdrawing groups at phenyl ring of the acetamide fragment contribute to the antitumour activity.     

Generation and cyclization of α-diazocarbothioimidates. Synthesis and structure of derivatives of 5-mercapto-1,2,3-triazole

The reaction of 5-amino-1,2,3-thiadiazol-4-carbothioamides with methyl iodide basically generates -diazo-S-methylthioimidates and -carbothioimidolates. It is shown that the reactivity of the latter increases when either alkyl or aryl substituents are introduced at the nitrogen atom of the carbothioamide groupTranslated from Khimiya Geterotsiklicheskikh Soedinenii, No. 7, pp. 979–984, July, 1992.     

Design, synthesis and antifungal activity of novel triazole derivatives

Twenty-three 1 -(1H-1,2,4-triazole-1 -y1)-2-(2,4-difluorophenyl)-3-(iV-cycloproyl-N-substituted-amino)-2-propanols were designed and synthesized on the basis of the active site of lanosterol 14α-demethylase. In vitro antifungal activities showed that some of the title compounds had higher antifungal activity and broader antifungal spectrum than fluconazole.     

Heterocyclic compounds as antiviral drugs: Synthesis,structure–activity relationship and traditional applications

A virus outbreak challenges the economic, medical, and public health infrastructure worldwide. More than one virus capable of triggering diseases have been identified per year since 1972, which requires the development of new ways of treatment and prevention, however, such processes are not rapid and easy. With the pandemic scenario experienced since early 2020, several drugs with well-known purposes have gained prominence, due to speculation of their use in the treatment against the new coronavirus. Among the main drugs studied, the vast majority contain a heterocyclic structure. In this review, we presented the traditional and efficient synthesis of 15 drugs that have been studied for the COVID-19 treatment, containing in their structure heterocycles like indole, quinoline, pyrimidone, tetrahydrofuran, pyrrolidine, triazole, pyridazine, pyrazole, pyrrolopyrimidine, azetidine, pyrrolotriazine, pyrazine, tetrahydropyran, benzofuran, spiroketal, and thiazole. Furthermore, we have shown the original applications, as well as their structure–activity relationship and what is their situation as a drug candidate against COVID-19. Thus, the objective was to consolidate the main synthetic and pharmacological aspects involving clinically developed heterocycles that at some point were presented as promising against SARS-CoV-2.     

Synthesis and antimicrobial activity of novel quinazolinone–thiazolidine–quinoline compounds

A series of 2-(2-chloroquinolin-3-yl)-5-((aryl)benzylidene)-3-(4-oxo-2-phenylquinazolin-3(4H)-yl)thiazolidin-4-ones (V)_1–12 have been synthesized. In order to establish optimization of different parameters of chemical transformation, that is the reaction pathway for each step and reaction conditions in the each step, in the present paper, different solvents and catalysts were used. The structures of the synthesized compounds were assigned on the basis of elemental analysis, IR, ¹H NMR and ¹³C NMR spectral data. All the newly synthesized compounds were screened against various strains of bacteria and fungi.     

Vanadiumoxo–aroylhydrazone complexes: Synthesis,structure and DFT calculations

The aroylhydrazone Schiff base ligands (E)-N’-(2-hydroxybenzylidene)benzohydrazide = H₂L¹, (E)-N’-(2-hydroxy-3-methoxybenzylidene)benzohydrazide = H₂L² and = (E)-N’-(5-bromo-2-hydroxybenzylidene)benzohydrazide = H₂L³ gave the vanadium(V)oxo-aroylhydrazone complexes [V^VOL¹(OCH₃)(OHCH₃] (1), [V^VOL²(OCH₃)(OHCH₃]·CH₃OH (2) and [V^VOL³(OCH₃)(OHCH₃] (3) on reaction with vanadium(IV) oxide acetylacetonate. The complexes were characterized by spectroscopic methods in the solid state (IR) and in solution (UV–Vis, ¹H NMR). Single crystal X-ray analysis was performed with 3. In methanol solution six-coordinated V^VOL³(OCH₃)(OHCH₃) was formed. V^IV was oxidized to V^v by aerial oxygen in the synthesis. In the VO₅N coordination sphere the alcohol oxygen lies trans to the oxo oxygen. The general V–O bond length order is oxo < methoxylato < phenoxidic < enolato < alcoholic. The complexes are mononuclear, but intermolecular O–H?N hydrogen bonding affords a zigzag chain. DFT calculations on complex 3 reproduced the geometric parameters, IR and UV–Vis spectroscopic data well in a reasonable range.     

Synthesis,characterization, and systematic structure–property investigation of a series of carbazole–thiophene derivatives

Russian Journal of General Chemistry - A series of carbazole–thiophene oligomers linked at the 3,6-positions of the carbazole fragment of 4,4′-bis(carbazol-9-yl)biphenyl (CBP) and...     

Synthesis, structure and biological activity of 3,7-dinitrodibenzobromonium salt

3,7-Dinitrodibenzobromonium bisulfate 3 was prepared directly by the reaction of4,4' -dinitrobiphenyl with sodium bromide and potassium persulfate in the concentrated sulphuric acid. Metathetical reactions of 3 gave 3, T-dinitrodibenzobromonium chloride 4, bromide 5 and iodide 6, respectively. Crystal structure of 3a obtained by crystallization of 3 in formic acid showed that each molecule of 3a consists of two dibenzobromonium ions, two bisulfate anions and a formic acid. The dibenzobromonium ion is nearly coplanar. Compound 3 can dramatically increase mice's immunofunction.