A study of fungicidal and anti-phenol oxidase activity of some α-amino phosphonate derivatives

Background Developing new pesticides with multi-function may be a suitable strategy to save time and cost and reduce the emergence of resistant strains of pests and pathogens. The organophosphorus derivatives have not been widely used in agriculture as fungicides. In this work, a series of six α-amino phosphonate derivatives were prepared and tested for their fungicidal and anti-phenol oxidase activities. Results The prepared compounds revealed a promising anti-fungal activity against Macrophomina phaseolina and Pythium aphanidermatum, especially M4, with MIC of 62 mg/L for M. phaseolina. M4 did not affect the fungus permeability rate of the cell membrane; however, it displayed a significant efficiency on mycelial soluble protein content. M4 and M3 with a hydroxyl group on the aniline moiety exhibited an observed anti-phenol oxidase activity. M4 inhibited the enzyme at 1 mg/mL. The DFT theoretical study revealed a significant correlation between the substituents of aniline moiety and the bioactivity of the studied compounds. The negative charge conspicuously influenced the anti-phenol oxidase activity. Conclusions Our findings suggest the studied compounds as bases to design more effective α-amino phosphonate fungicides with additional anti-phenol oxidase activity. Graphic abstract

Research on the Interaction Mechanism Between α Mino-Phosphonate Derivative Q-R and Harpin-Binding Protein 1 in Tobacco (Nicotiana tabacum) Plants

Amino-phosphonate derivative R-diphenyl-1-(4-methylbenzothiazole-2-amino)-1-(thiphene-2-yl)-methylphosphonate (Q-R) has a high protective anti-tobacco mosaic virus (TMV) activity. However, the mechanism responsible for Q-R’s effect on TMV infection is largely unknown. Here, we studied the expression levels of harpin-binding protein 1 (HrBP1) and pathogenesis-related protein-1a (PR-1a) in TMV-infected tobacco plants by using reverse transcription quantitative real-time PCR. Then, we verified the interactions between Q-R and the HrBP1 protein from Escherichia coli using isothermal titration calorimetry and studied the Q-R-associated assembly of HrBP1 using size-exclusion chromatography. The results showed that the expression levels of HrBP1 and PR-1a genes were significantly increased by Q-R at the transcriptional level in TMV-infected tobacco plants, and the E. coli-expressed HrBP1 protein was assembled into oligomers by Q-R via binding to HrBP1 with a dissociation constant of 1.19 μM. We, therefore, concluded that Q-R activated the HrBP1 and PR-1a genes and enhanced the ability of HrBP1 to assemble in tobacco plants.

Synthesis, Crystal Structure and Interaction with Bovine Serum Albumin (BSA) of Two α-Aminophosphonic Acids Derivatives

Two α-amino-phosphonate derivatives (1 & 2) were synthesized and their compositions and structures were characterized by Elemental Analysis (EA), FT-IR Spectrascopy (FT-IR), Electrospray Ionization Mass Spectrometry (ESI-MS), Nuclear Magnetic Resonance (NMR, 1H, 13C and 31P) and X-ray crystallography. Compound 1 & 2 were crystallized in monoclinic system with the space group P2(1)/n and P2(1)/c, respectively. The interaction effects of two α-aminophosphonate derivatives (1 & 2) with BSA were investigated and the binding constants were 1.07 × 104 M-1, 1.68 × 104 M-1, respectively. Besides, the values of n were indicated that 1:1 complex was formed between BSA and 1&2.

Anti-Protozoal Potential of Heterocyclic Compounds Against Giardiasis

The aim of this literature review is to compile data of heterocyclic antigiardial agents. The importance is to analyze the structural requirements for improved antigiardial activity, to overcome resistance and enhance the bioavailability of the compounds under study. Though, nitroimidazoles/ imidazoles and benzimidazoles are major classes, other heterocyclic scaffolds viz. oxoindolinylidene, dioxodihydroisobenzofuran-5-carboxamide, fluoroquinolone, thieno[2,3-b]pyridine- 5-carbonitrile, α-amino-phosphonate analogs of polyoxins, nitazoxanide benzologue, thiazole and triazolyl- quinolone chalcone also possess activity against Giardia species. Heterocyclic phytoconstituents are also included to have a deep idea of antigiardial activity of herbs possessing heterocyclic constituents.

Monosubstituted pillar[5]arene functionalized with (amino)phosphonate fragments are “smart” building blocks for constructing nanosized structures with some s- and p-metal cations in the organic phase

Pillar[5]arenes with phosphonate- and 1-aminophosphonate-substituents form complexes with Na+, K+, Cs+ and Pb2+ with a 1 : 1 stoichiometry and lg Ka values between 2.0 and 4.8, and that Pb2+ is the most effectively bound cation.

Ultrasound Assisted Synthesis of Diethyl (2-(1-(morpholinomethyl)-2-Oxoindolin-3-ylidene)hydrazinyl) (Substituted Phenyl/heteryl) MethylphosphonateDerivatives

This work reports ultrasound assisted synthesis diethyl (2-(1-(morpholinomethyl)-2-oxoindolin-3-ylidene)hydrazinyl) (substituted phenyl/heteryl) methylphosphonate 9(a–j) derivatives. The derivatives are synthesized using a green protocol. In the first step, 3-hydrazonoindolin-2-one is synthesized using ultrasound. In the second step, diethyl (substituted phenyl/heteryl)(2-(2-oxoindolin-3-ylidene)hydrazinyl) methylphosphonate 6(a–j) derivatives are synthesized using cerric ammonium nitrate as catalyst. In the third step, diethyl (2-(1-(morpholinomethyl)-2-oxoindolin-3-ylidene)hydrazinyl) (substituted phenyl/heteryl) methylphosphonate 9(a–j) derivatives are synthesized using ultrasound. Isatin, chemically known as H-indole-2,3-dione, and its derivatives possess a broad range of biological and pharmacological properties. Isatin is widely used as a starting material for the synthesis of a broad range of heterocyclic compounds and as substrates for drug synthesis. The α-amino phosphonate derivatives constitute an important class of organophosphorus compounds on account of their versatile biological activity. Morpholine moiety has been found to be an eminent pharmacophore in medicinal chemistry. A number of molecules possessing morpholine moiety are clinically approved drugs. The importance of this ring is well understood by medicinal chemists, since they play a major role in molecular properties such as an electronic distribution, three dimensionality, scaffold flexibility/rigidity, lipophilicity or polarity and metabolic stability. Considering the importance of the three pharmacophores, this promoted us to club these pharmacophores together in a single molecule using a green synthetic protocol.The structures of the ultrasound synthesized compounds were confirmed by spectral analysis like IR, 1H NMR, 13C NMR, 31P NMR and MS.