scholarly journals Synthesis, Characterization, In Vitro and In Vivo Screening of Unsymmetrical Borole Complexes of 2-Hydroxy-N-Phenylbenzamide and its Derivatives

2000 ◽  
Vol 7 (1) ◽  
pp. 7-16 ◽  
Author(s):  
Taruna Pandey ◽  
R. V. Singh

Biochemical aspects, synthesis and characterization of some boron complexes of 2-hydroxy-N-phenylbenzamide (HOPhBenz) and its semicarbazone (HOPhBenz.SCZH) and thiosemicarbazone (HOPhBenz.TSCZH) are described. These derivatives were prepared by the reactions of 2-isopropoxy-4-methyl-1,3,2-dioxaborolane, and 2-isopropoxy-4-methyl-1,3,2-dioxaborinane with 2-hydroxy-N-phenylbenzamide, 1-[(2-hydroxyphenyl)-1-N-phenylamino]hydrazinecarboxamide (HOPhBenz.SCZH), and 1-[(2-hydroxyphenyl)-1-N-phenylamino]hydrazinecarbothioamide(HOPhBenz.TSCZH) in a 1:1 molar ratio. In order to assess the increase of the inhibitor potency, (HOPhBenz), (HOPhBenz.SCZH), (HOPhBenz.TSCZH) and their boron complexes have been tested in vitro against a number of pathogenic fungi and bacteria at different concentrations and were found to possess remarkable fungicidal and bactericidal properties. The testicular sperm density, testicular sperm morphology, sperm motility, density of cauda epididymal spermatozoa and fertility in mating trials and biochemical parameters of reproductive organs are discussed.

2000 ◽  
Vol 7 (5) ◽  
pp. 237-243 ◽  
Author(s):  
Kripa Sharma ◽  
S. C. Joshi ◽  
R. V. Singh

A new series of unsymmetrical macrocyclic complexes of tin(ll) has been prepared by the template process using bis(3-oxo-2-butylidene)propane-1,3-diamine as precursor. This affords a method to synthesize these complexes with various ring sizes. The tetradentate macrocyclic precursor [N4mL] reacts with SnCl2 and different diamines in a 1:1:1 molar ratio in refluxing methanol to give complexes of the type [Sn(N4mL)Cl2]. The ring expansion has been achieved by varying the diamine between the two diacetyl amino nitrogen atoms. The macrocyclic precursor and its metal complexes have been characterized on the basis of elemental analysis, molar conductance, molecular weight determinations, IR, H1 NMR,C13 NMR, Sn119 NMR and electronic spectral studies. An octahedral geometry around the metal ion is suggested for these complexes. On the basis of molecular weights and conductivity measurements, their monomeric and non-electrolytic nature has been confirmed. The precursor and complexes have been screened in vitro against a number of pathogenic fungi and bacteria to assess their growth inhibiting potential. The testicular sperm density and testicular sperm morphology, sperm motility, density of cauda epididymal spermatozoa and fertility in mating trails and biochemicals parameters of reproductive organs have been examined and discussed.


2002 ◽  
Vol 8 (6) ◽  
pp. 347-353 ◽  
Author(s):  
Ashu Chaudhary ◽  
D. P. Jaroli ◽  
R. V. Singh

Some antifertility inhibitors of 18 to 24-membered tetraazamacrocyclic complexes of iron(II) and manganese(II) have been synthesised by the template condensation using 1,3-phenylenediamine with malonic acid, succinic acid, glutaric acid and adipic acid. The reaction proceed smoothly to completion. The complexes were characterized by elemental analyses, molecular weight determinations, infrared, electronic, magnetic moment, mössbaur and mass spectral studies. The elemental analyses are consistent with the formation of the complexes [M(N4Ln)Cl2] (M = Fe(lI) or Mn(II)). All these complexes are stable and monomeric in nature as indicated by the molecular weight determinations. The spectral studies confirm the octahedral geometry around the central metal atom. The complexes have been screened in vitro against a number of fungi and bacteria to assess their growth inhibiting potential. The testicular sperm density and testicular sperm morphology, sperm motility, density of cauda epididymal spermatozoa and fertility in mating trials and biochemical parameters of reproductive organs have been examined and discussed.


2001 ◽  
Vol 8 (3) ◽  
pp. 149-158 ◽  
Author(s):  
R. V. Singh ◽  
S. C. Joshi ◽  
Shalini Kulshrestha ◽  
Pooja Nagpal ◽  
Anil Bansal

Synthesis, characterization and antimicrobial activities of an interesting class of biologically potent macrocyclic complexes have been carried out. All the complexes have been evaluated for their antimicrobial effects on different species of pathogenic fungi and bacteria. The testicular sperm density, testicular sperm morphology, sperm motility, density of cauda epididymal spermatozoa and fertility in mating trails and biochemical parameters of reproductive organs have been examined and discussed. The resulting biologically active [M(MaLn)(R2)]Cl2 and [Pb(MaLn)(R2)X2] (where, M = PdII or PtII and X = Cl or NO3) type of complexes have been synthesized by the reactions of macrocyclic ligands (MaLn) with metal salts and different diamines in 1:1:1 molar ratio in methanol. Initially the complexes were characterized by elemental analyses, molecular weight determinations and conductivity measurements. The mode of bonding was established on the basis of IR, H1 NMR, C13 NMR, Pt195 NMR, Pb207 NMR, XRD and electronic spectral studies. The macrocyclic ligand coordinates through the four azomethine nitrogen atoms which are bridged by benzil moieties. IR spectra suggest that the pyridine nitrogen is not coordinating. The palladium and platinum complexes exhibit tetracoordinated square-planar geometry, whereas a hexacoordinated octahedral geometry is suggested for lead complexes.


1994 ◽  
Vol 107 (10) ◽  
pp. 2839-2849 ◽  
Author(s):  
J.C. Bulinski ◽  
A. Bossler

In previous studies (Bulinski and Borisy (1979). Proc. Nat. Acad. Sci. 76, 293–297; Weatherbee et al. (1980). Biochemistry 19, 4116–4123) a microtubule-associated protein (MAP) of M(r) approximately 125,000 was identified as a prominent MAP in HeLa cells. We set out to perform a biochemical characterization of this protein, and to determine its in vitro functions and in vivo distribution. We determined that, like the assembly-promoting MAPs, tau, MAP2 and MAP4, the 125 kDa MAP was both proteolytically sensitive and thermostable. An additional property of this MAP; namely, its unusually tight association with a calcium-insensitive population of MTs in the presence of taxol, was exploited in devising an efficient purification strategy. Because of the MAP's tenacious association with a stable population of MTs, and because it appeared to contribute to the stability of this population of MTs in vitro, we have named this protein ensconsin. We examined the binding of purified ensconsin to MTs; ensconsin exhibited binding that saturated its MT binding sites at an approximate molar ratio of 1:6 (ensconsin:tubulin). Unlike other MAPs characterized to date, ensconsin's binding to MTs was insensitive to moderate salt concentrations (< or = 0.6 M). We further characterized ensconsin in immunoblotting experiments using mouse polyclonal anti-ensconsin antibodies and antibodies reactive with previously described MAPs, such as high molecular mass tau isoforms, dynamin, STOP, CLIP-170 and kinesin. These experiments demonstrated that ensconsin is distinct from other proteins of similar M(r) that may be present in association with MTs. Immunofluorescence with anti-ensconsin antibodies demonstrated that ensconsin was detectable in association with most or all of the MTs of several lines of human epithelial, fibroblastic and muscle cells; its in vivo properties and distribution, especially in response to drug or other treatments of cells, were found to be different from those of MAP4, the predominant MAP found in these cell types. We conclude that ensconsin, a MAP found in a variety of human cells, is biochemically - and perhaps functionally - distinct from other MAPs present in non-neuronal cells.


2000 ◽  
Vol 7 (2) ◽  
pp. 105-113 ◽  
Author(s):  
Kripa Sharma ◽  
S. C. Joshi ◽  
R. V. Singh

Synthetic, spectroscopic and antimicrobial aspects of some fertility inhibitor heterobimetallic complexes have been carried out. These heterobimetallic chelates [M(C5H5N3)2M2'(R)4]Cl2 (M = Pd or Pt and M' = Si, Sn, Ti and Zr) have been successfully synthesinzed via the reaction of M(C5H7N3)2Cl2 with group four or fourteen dichlorides in 1:2 stoichiometric proportions. The products were characterized by elemental analyses, molecular weight determinations, magnetic susceptibility measurements, conductance, and IR multinuclear NMR and electronic spectral studies. A square planar geometry has been suggested for all the complexes with the help of spectral data. Conductivity data strongly suggest that chlorine atoms are ionic in nature due to which complexes behave as electrolytes. All the complexes have been evaluated for their antmicrobial effects on different species of pathogenic fungi and bacteria. The testicular sperm density, testicular sperm morphology, sperm motility, density of cauda epididymal spermatozoa and fertility in mating trails and biochemical parameters of reproductive organs have been examined and discussed.


2019 ◽  
Author(s):  
Priya Prakash ◽  
Travis Lantz ◽  
Krupal P. Jethava ◽  
Gaurav Chopra

Amyloid plaques found in the brains of Alzheimer’s disease (AD) patients primarily consists of amyloid beta 1-42 (Ab42). Commercially, Ab42 is synthetized using peptide synthesizers. We describe a robust methodology for expression of recombinant human Ab(M1-42) in Rosetta(DE3)pLysS and BL21(DE3)pLysS competent E. coli with refined and rapid analytical purification techniques. The peptide is isolated and purified from the transformed cells using an optimized set-up for reverse-phase HPLC protocol, using commonly available C18 columns, yielding high amounts of peptide (~15-20 mg per 1 L culture) in a short time. The recombinant Ab(M1-42) forms characteristic aggregates similar to synthetic Ab42 aggregates as verified by western blots and atomic force microscopy to warrant future biological use. Our rapid, refined, and robust technique to purify human Ab(M1-42) can be used to synthesize chemical probes for several downstream in vitro and in vivo assays to facilitate AD research.


Carbon ◽  
2016 ◽  
Vol 103 ◽  
pp. 291-298 ◽  
Author(s):  
Valeria Ettorre ◽  
Patrizia De Marco ◽  
Susi Zara ◽  
Vittoria Perrotti ◽  
Antonio Scarano ◽  
...  

Microbiology ◽  
2006 ◽  
Vol 152 (7) ◽  
pp. 2129-2135 ◽  
Author(s):  
Taku Oshima ◽  
Francis Biville

Functional characterization of unknown genes is currently a major task in biology. The search for gene function involves a combination of various in silico, in vitro and in vivo approaches. Available knowledge from the study of more than 21 LysR-type regulators in Escherichia coli has facilitated the classification of new members of the family. From sequence similarities and its location on the E. coli chromosome, it is suggested that ygiP encodes a lysR regulator controlling the expression of a neighbouring operon; this operon encodes the two subunits of tartrate dehydratase (TtdA, TtdB) and YgiE, an integral inner-membrane protein possibly involved in tartrate uptake. Expression of tartrate dehydratase, which converts tartrate to oxaloacetate, is required for anaerobic growth on glycerol as carbon source in the presence of tartrate. Here, it has been demonstrated that disruption of ygiP, ttdA or ygjE abolishes tartrate-dependent anaerobic growth on glycerol. It has also been shown that tartrate-dependent induction of the ttdA-ttdB-ygjE operon requires a functional YgiP.


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