Thymol and its Derivatives for Management of Phytopathogenic fungi of maize

Background: Thymol is a bioactive compound having many pharmacological activities. Objective: The present study was carried out to evaluate the fungi toxic effects of thymol and derivatives against phytopathogenic fungi of maize. Method: Thymol was derivatized to get formylated thymol, Mannich bases, and imine derivatives. All the synthesized thymol derivatives were characterized by their physical and spectral properties. Synthesized thymol derivatives were screened for their in vitro antifungal effects using poisoned food technique against three maize pathogenic fungi namely Fusarium moniliforme, Rhizoctonia solani and Dreschlera maydis. Results: Thymol and formylated thymol showed promising results for control of D. maydis with ED50 values less than standard carbendazim and comparable to standard mancozeb. These two compounds were further evaluated for control of D. maydis causative maydis leaf blight disease on maize plants grown in the field during the Kharif season (June to October) 2018. Conclusion: Thymol exhibited significant control of maydis leaf blight disease of maize and emerged as a potential alternative to synthetic fungicides used in cereal crops.

Mannich Bases: Centrality in Cytotoxic Drug Design

: Mannich bases identified by Professor Carl Mannich have been the most extensively explored scaffolds for more than 100 years now. The versatile biological roles that they play have promoted their applications in many clinical conditions. The present review highlights the application of Mannich bases as cytotoxic agents, categorizing them into synthetic, semisynthetic and prodrugs classes and gives an exhaustive account of the work reported in the last two decades. The methods of synthesis of these cytotoxic agents, their anti-cancer potential in various cell lines and promising leads for future drug development have also been discussed. Structure-activity relationships along with the targets on which these cytotoxic Mannich bases act have been included as well.

ULTRASOUND-ASSISTED SYNTHESIS OF NOVEL 3-(PYRIDINYLAMINO)-1-FERROCENYLPROPAN-1-ONES

In this work we will report the formulation of novel 3-(pyridinylamino)-1-ferrocenylpropan-1-ones. A fruitful aza-Michael addition of pyridinamine moiety to a conjugated enone, 1-ferrocenylpropenone, has been accomplished by an ultrasonic irradiation of the mixture of these reactants. As the catalyst montmorillonite K-10 has been used and the reaction has been carried out as solvent-free, yielding ferrocene containing Mannich bases, compounds considered as important precursors in organic synthesis. The reaction score has been evaluated on three examples. The prepared products have been purified by column chromatography. In addition, a detailed characterization of the obtained 3-(pyridin-2-ylamino)-1-ferrocenylpropan-1-on and 3-(pyridin-3-ylamino)-1-ferrocenylpropan-1-on has been completed by IR and NMR spectroscopy, as well as elemental analyses.

Preparation,Characterization and Study of Biological Activity for some new derivatives Mannich's bases derived from Shiff's bases

This paper involves synthesis new Mannich bases derived from Shiff' bases which prepared from isatin by the reaction of isatin with different aromatic amines to prepare Shiff bases derivatives (M, G, B, R, X, S), then Shiff's bases derivatives reacted with formaldehyde and piperazine to produce Mannich bases derivatives (M1, G1, B1, R1, X1, S1). The third step included the assay of biological activity of all compounds against four types of pathogens bacteria (Staphylococcus aureus, Granutice tella adiacens) gram positive and (E. coli, Proteus mirabilis) gram negative the results exhibited excellent biological activity for all derivatives compared to antibiotics (Ampicillin and Ciprofloxacin) these structures were identified by FT-IR,1HNMRand 13CNMR.

Synthesis and antitumor activities of novel Mannich base derivatives derived from natural flavonoids

In our current study, a series of reactions with isolated natural flavonoids (2-phenylchromen-4-one) and flavanone (2,3-dihydro-2-phenylchromen-4-one) through Mannich base was carried out by a one-pot three-component reaction. Their structure-activity relationship study (SAR) reveals the anticancer activity of natural compounds and their Mannich bases. The flavones were substituted by imine at position C-8, while in the flavanones, the reaction takes place at positions C-8 and C-3. Spectroscopic techniques characterized all the isolated and newly synthesized derivatives. Anticancer activity was checked on HeLa and MCF-7 (cancer cell lines) and BHK-21 (normal cell line). Using propidium iodide (PI) and DAPI staining as fluorescence microscopic imaging was confirmed the Apoptotic effect of potent compound. Further, it was evaluated by cell cycle analysis through flow-cytometry, reactive oxygen species and lactate dehydrogenase production. The caspase-9 and -3 activity were estimated by mitochondrial membrane potential. Derivative of naringenin, ((2S)-4′,5,7-Trihydroxyflavan-4-one) where reactions occur at position C-3 were active than others.

Synthesis, Characterization and Study of Antimicrobial Activities of Mannich Bases Incorporating 1,2,4-Triazole Nucleus

Heterocyclic compounds containing triazole moiety have great importance in the field of medicine, pharmaceuticals, biochemistry, biology, therapeutics, environmental science, and industry. Triazoles and their derivatives have been extensively used in the development of new drugs. Biological activities of Schiff bases are highly investigated, but Mannich bases are on the verge of their development, and they are being synthesized in large number nowadays. In this work, Mannich bases are synthesized by incorporation 1,2,4-triazole moiety through Schiff base using different amines. Mannich bases are found to exhibit highly effective antibacterial and antifungal activities. The formation of synthesized compounds - 1,2,4-triazole-5-thione, Schiff base (4) and Mannich bases (5a and 5b) - are confirmed and characterized by spectroscopic techniques like UV, FTIR 1H-NMR and 13C-NMR. The activity of the synthesized compounds was tested against bacterial and fungal strain.

SYNTHESIS, BIOLOGICAL STUDY, DNA INTERACTION OF MANNICH BASE METAL COMPLEXES DERIVED FROM BENZAMIDE

Objective: Coordination compounds occur widely in nature and they comprise a large share of current inorganic research. The Mannich reaction is a classic method for the preparation of Mannich bases, namely, β amino compounds, which are heterocyclic. Methods: A novel Mannich base of N-((3,4-dimethoxyphenyl)(2,5-dioxopyrrolidin-1-yl) methyl)benzamide and its coordination complexes with transition metals Mn and Co have been synthesized and characterized by elemental analysis, molar conductance, magnetic susceptibility measurements, UV-Visible, IR, NMR, and Mass spectral studies. Results: Based on the magnetic moment and UV-Visible spectral data, octahedral geometries were assigned for the metal complexes. The metal complexes were screened for antifungal activity. Conclusion: the metal complexes have shown good activity than the ligand. The binding of selected metal complexes with calf thymus DNA was investigated. It is found that the cobalt (II) metal complex of the ligand showed efficient DNA binding ability.