Inhibition of Amphiphilic N-Alkyl-O-carboxymethyl Chitosan Derivatives on Alternaria macrospora

Cotton leaf spot (Alternaria macrospora) is a widespread disease that occurs in the main cotton-producing area of China. In managing this disease, a novel chitosan-based biopesticide, an amphiphilic N-alkyl-O-carboxymethyl chitosan derivative, was prepared. The product was selected from variations of chitosan with different molecular structures, which were obtained via a two-step reaction. First, carboxymethyl chitosans with varying molecular sizes were obtained by etherification with chloroacetic acid; then the carboxymethyl chitosan was alkylated with C4–C12 fatty aldehyde through a Schiff-base reaction. This procedure resulted in derivatives of amphiphilic N-alkyl-O-carboxymethyl chitosan, which showed strong antifungal activities against A. macrospora, and the efficacy was determined by its molecular structure.

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Synthesis and Molecular Structure of Stable Derivatives of (E)- and (Z)-Dehydrophenylalanine

Australian Journal of Chemistry ◽

10.1071/ch9910687 ◽

1991 ◽

Vol 44 (5) ◽

pp. 687 ◽

Cited By ~ 10

Author(s):

CJ Easton ◽

CA Hutton ◽

PD Roselt ◽

ERT Tiekink

Keyword(s):

Molecular Structure ◽

Crystallographic Analysis ◽

Molecular Structures ◽

X Ray ◽

Isomeric Pair ◽

Derivatives Of

Bromination of the phenylalanine derivative (1) affords the bromides (2) and (3), which react by stereospecific anti-elimination to give the isomeric pair of stable dehydrophenylalanine derivatives (4) and (5). The molecular structures of (4)and (5), which have been determined by X-ray crystallographic analysis, correlate with their lack of interconversion and the unusual stability of (5).

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Preparation of O-Carboxymethyl Chitosan by Schiff Base and Antibacterial Activity

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.647.794 ◽

2013 ◽

Vol 647 ◽

pp. 794-797 ◽

Cited By ~ 5

Author(s):

Ying Liu ◽

Di Zhao ◽

Jiang Tao Wang

Keyword(s):

Schiff Base ◽

Elemental Analysis ◽

Chloroacetic Acid ◽

Antimicrobial Activities ◽

Carboxymethyl Chitosan ◽

Ft Ir ◽

Novel Method ◽

And Staphylococcus Aureus ◽

Better Than ◽

Ft Ir Spectroscopy

A novel method of preparation O-Carboxymethyl chitosan (OCMC) was studied that the product was prepared by reaction of Schiff's base of chitosan. Schiff base of chitosan (BCTS) was synthesized by the reaction of chitosan with aromatic aldehyde, then BCTS reacted with chloroacetic acid and removed the group of amino protection to get the target product. The chitosan derivative was characterized by FT-IR spectroscopy, 1HNMR and elemental analysis. Elemental analysis results confirmed that the degree of substitution(DS) of OCMC was 0.83. Solubility of OCMC in water and organic solvents was demonstrated to be better than that of chitosan. The antimicrobial activities of chitosan and OCMC were investigated against Aspergillus niger and Staphylococcus aureus. The results indicate that the antimicrobial activity of OCMC was superior to chitosan.

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Synthesis, structural characterization and catalytic activity of chlororuthenium(II) complexes with substituted Schiff base/phosphine ancillary ligands

Zeitschrift für Naturforschung B ◽

10.1515/znb-2020-0110 ◽

2020 ◽

Vol 75 (9-10) ◽

pp. 851-857

Author(s):

Chong Chen ◽

Fule Wu ◽

Jiao Ji ◽

Ai-Quan Jia ◽

Qian-Feng Zhang

Keyword(s):

Schiff Base ◽

Catalytic Activity ◽

Structural Characterization ◽

Room Temperature ◽

Molecular Structures ◽

Cationic Complex ◽

Neutral Complex ◽

Ancillary Ligands ◽

X Ray ◽

X Ray Crystallography

AbstractTreatment of [(η6-p-cymene)RuCl2]2 with one equivalent of chlorodiphenylphosphine in tetrahydrofuran at reflux afforded a neutral complex [(η6-p-cymene)RuCl2(κ1-P-PPh2OH)] (1). Similarly, the reaction of [Ru(bpy)2Cl2·2H2O] (bpy = 2,2′-bipyridine) and chlorodiphenylphosphine in methanol gave a cationic complex [Ru(bpy)2Cl(κ1-P-PPh2OCH3)](PF6) (2), while treatment of [RuCl2(PPh3)3] with [2-(C5H4N)CH=N(CH2)2N(CH3)2] (L1) in tetrahydrofuran at room temperature afforded a ruthenium(II) complex [Ru(PPh3)Cl2(κ3-N,N,N-L1)] (3). Interaction of the chloro-bridged complex [Ru(CO)2Cl2]n with one equivalent of [Ph2P(o-C6H4)CH=N(CH2)2N(CH3)2] (L2) led to the isolation of [Ru(CO)Cl2(κ3-P,N,N-L2)] (4). The molecular structures of the ruthenium(II) complexes 1–4 have been determined by single-crystal X-ray crystallography. The properties of the ruthenium(II) complex 4 as a hydrogenation catalyst for acetophenone were also tested.

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Structural Characterization of Heterodinuclear ZnII-LnIII Complexes (Ln = Pr, Nd) with a Ring-Contracted H2valdien-Derived Schiff Base Ligand

Journal of Chemical Crystallography ◽

10.1007/s10870-021-00891-4 ◽

2021 ◽

Author(s):

Shabana Noor ◽

Richard Goddard ◽

Fehmeeda Khatoon ◽

Sarvendra Kumar ◽

Rüdiger W. Seidel

Keyword(s):

Molecular Structure ◽

Schiff Base ◽

Structural Characterization ◽

Schiff Base Ligand ◽

Crystal And Molecular Structure ◽

X Ray ◽

X Ray Crystallography ◽

Imidazoline Ring

AbstractSynthesis and structural characterization of two heterodinuclear ZnII-LnIII complexes with the formula [ZnLn(HL)(µ-OAc)(NO3)2(H2O)x(MeOH)1-x]NO3 · n H2O · n MeOH [Ln = Pr (1), Nd (2)] and the crystal and molecular structure of [ZnNd(HL)(µ-OAc)(NO3)2(H2O)] [ZnNd(HL)(OAc)(NO3)2(H2O)](NO3)2 · n H2O · n MeOH (3) are reported. The asymmetrical compartmental ligand (E)-2-(1-(2-((2-hydroxy-3-methoxybenzylidene)amino)-ethyl)imidazolidin-2-yl)-6-methoxyphenol (H2L) is formed from N1,N3-bis(3-methoxysalicylidene)diethylenetriamine (H2valdien) through intramolecular aminal formation, resulting in a peripheral imidazoline ring. The structures of 1–3 were revealed by X-ray crystallography. The smaller ZnII ion occupies the inner N2O2 compartment of the ligand, whereas the larger and more oxophilic LnIII ions are found in the outer O2O2’ site. Graphic Abstract Synthesis and structural characterization of two heterodinuclear ZnII-LnIII complexes (Ln = Pr, Nd) bearing an asymmetrical compartmental ligand formed in situ from N1,N3-bis(3-methoxysalicylidene)diethylenetriamine (H2valdien) through intramolecular aminal formation are reported.

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