The objective of this study was to investigate the antibacterial activity and potential mechanism alkyl gallates against Escherichia coli Staphylococcus aureus. Results show that length chain plays a pivotal role in eliciting octyl gallate (OG) exerted excellent bactericidal through multiple mechanism. OG functions both bacteria damaging bacterial cell wall integrity, permeating into cells then...

A number of fluoroquinolone derivatives were synthesized and evaluated for antimycobacterial activity. Preliminary results are (1) for 1-aryl fluoroquinolones, 1-(4-nitrophenyl) derivatives were inactive while their 1-(2-fluoro-4-nitrophenyl) counterparts were active anti-TB agents (3a vs 4a; 3b vs 4b) indicated the fluoro substituent at C-2 position is important. For the 1-(2-fluoro-4-nitrophe...

Coumarin is classified as one of interesting therapeutic starting research points to obtain remarkable compounds with high efficacy. So, during this research, new 2-iminochromene derivatives bearing coumarin moiety were synthesized. At first, cyanoacetohydrazone 3-acetylcoumarin was prepared and used the material. The synthesized through ring closure derivative 4-hydroxysalicylaldehyde, 5-aryld...

A new flavonol galactopyranoside, myricetin 3-O-(2'',3''-digalloyl)-β-D-galactopyranoide (1), and 23 known constituents, including myricetin 3-O-(2''-galloyl)-β-D-galactopyranoide (2), myricitrin (3), myricetin (4), quercetin 3-O-(2'', 3''-digalloyl)-β-D-galactopyranoide (5), quercetin 3-O-(2''-galloyl)-β-D-galactopyranoide (6), hyperin (7), isoquercetrin (8), quercetin (9), kaempferol (10), ap...

• Connections in Rn . We have by now defined a number of different notions of differentiation: the differential of maps between manifolds, the exterior derivative of differential forms, and the Lie derivative. To begin to see the need for a new notion of differentiation (which will turn out to be the most fundamental and will apply to general tensor fields) consider first the problem of definin...

2-Acetyl-5,6,7,8-tetrahydronaphthalene (1) was allowed to react with different aromatic aldehydes to produce the cyanopyridones 2a and 2b, which were treated with phosphorous pentasulfide to afford the corresponding thioxopyridine derivatives 3a and 3b, respectively. The reaction of 3a and 3b with ethyl bromoacetate afforded the ester derivatives 4a and 4b, while their condensation with hydrazi...

We survey recent results on the structure of the range of the derivative of a smooth mapping f between two Banach spaces X and Y . We recall some necessary conditions and some sufficient conditions on a subsetA of (X ,Y) for the existence of a Fréchet differentiable mapping f from X into Y so that f ′(X)= A. Whenever f is only assumed Gâteaux differentiable, new phenomena appear: for instance, ...

approximating the solution of differential equations of fractional order is necessary because fractional differential equations have extensively been used in physics, chemistry as well as engineering fields. in this paper with central difference approximation and newton cots integration formula, we have found approximate solution for a class of boundary value problems of fractional order. three...

potential field methods such as gravity and magnetic methods are among the most applied geophysical methods in mineral exploration. a high-resolution technique is developed to image geologic boundaries such as contacts and faults. potential field derivatives are the basis of many interpretation techniques. in boundary detection, the analytic signal quantity is defined by combining the val...

When a hot aqueous extract of black tea cools down, a colloidal complex (tea cream) is formed, which poses technological problems in industrial processes e.g. manufacture of instant tea and tea cordials. Removal of 'tea cream' by centrifugation leaves the residual liquor stripped to a great extent of the desirable characteristics of tea. The studies on the nature of tea cream, the mechanics of ...