scholarly journals Synthesis of Cyclic Derivatives of Tartaric Acid by Condensing Alkyld-Tartrates with Aromatic Aldehydes. (Optical Activity and Chemical Structure in Tartaric Acid. VI)

1939 ◽  
Vol 14 (2) ◽  
pp. 35-40 ◽  
Author(s):  
Yojiro Tsuzuki
Keyword(s):  
Tartaric Acid ◽  
Optical Activity ◽  
Chemical Structure ◽  
Aromatic Aldehydes ◽  
Derivatives Of

Synthesis and Kinetics of Highly Substituted Piperidines in the Presence of Tartaric Acid as a Catalyst

2018 ◽  
Vol 21 (4) ◽  
pp. 302-311
Author(s):  
Younes Ghalandarzehi ◽  
Mehdi Shahraki ◽  
Sayyed M. Habibi-Khorassani
Keyword(s):  
Ambient Temperature ◽  
Tartaric Acid ◽  
Aromatic Aldehydes ◽  
One Pot ◽  
Rate Determining Step ◽  
State Approximation ◽  
Solvent Free Conditions ◽  
Steady State Approximation ◽  
Absorbance Changes ◽  
The One

Aim & Scope: The synthesis of highly substituted piperidine from the one-pot reaction between aromatic aldehydes, anilines and β-ketoesters in the presence of tartaric acid as a catalyst has been investigated in both methanol and ethanol media at ambient temperature. Different conditions of temperature and solvent were employed for calculating the thermodynamic parameters and obtaining an experimental approach to the kinetics and mechanism. Experiments were carried out under different temperature and solvent conditions. Material and Methods: Products were characterized by comparison of physical data with authentic samples and spectroscopic data (IR and NMR). Rate constants are presented as an average of several kinetic runs (at least 6-10) and are reproducible within ± 3%. The overall rate of reaction is followed by monitoring the absorbance changes of the products versus time on a Varian (Model Cary Bio- 300) UV-vis spectrophotometer with a 10 mm light-path cell. Results: The best result was achieved in the presence of 0.075 g (0.1 M) of catalyst and 5 mL methanol at ambient temperature. When the reaction was carried out under solvent-free conditions, the product was obtained in a moderate yield (25%). Methanol was optimized as a desirable solvent in the synthesis of piperidine, nevertheless, ethanol in a kinetic investigation had none effect on the enhancement of the reaction rate than methanol. Based on the spectral data, the overall order of the reaction followed the second order kinetics. The results showed that the first step of the reaction mechanism is a rate determining step. Conclusion: The use of tartaric acid has many advantages such as mild reaction conditions, simple and readily available precursors and inexpensive catalyst. The proposed mechanism was confirmed by experimental results and a steady state approximation.

scholarly journals Synthesis and biological activity of 4-thiazolidinone derivatives of phenothiazine

2012 ◽  
Vol 77 (1) ◽  
pp. 17-26 ◽  
Author(s):  
Ritu Sharma ◽  
Pushkal Samadhiya ◽  
Savitri Srivastava ◽  
Santosh Srivastava
Keyword(s):  
Antimicrobial Activity ◽  
Heterocyclic Compounds ◽  
Thioglycolic Acid ◽  
Cycloaddition Reaction ◽  
Aromatic Aldehydes ◽  
Knoevenagel Reaction ◽  
Antituberculosis Activity ◽  
Bacteria And Fungi ◽  
Derivatives Of ◽  
Anhydrous Zncl2

A new series of N-[3-(10H-phenothiazinyl)-propyl]-2-(substituted phenyl)-4-oxo-5-( substituted benzylidene)-1,3-thiazolidine-carboxamide, 5(as) have been synthesized. The cycloaddition reaction of thioglycolic acid with N-[3-(10H-phenothiazinyl)-propyl]-N?-[(substituted phenyl)-methylidene]- urea, 3(a-s) in the presence of anhydrous ZnCl2 afforded new heterocyclic compounds N-[3-(10H-phenothiazinyl)-propyl]-2-(substituted phenyl)-4-oxo- 1,3-thiazolidine-carboxamide, 4(a-s). The later product on treatment with several selected substituted aromatic aldehydes in the presence of C2H5ONa undergoes Knoevenagel reaction to yield 5(a-s). The structure of compounds 1, 2, 3(a-s), 4(a-s) and 5(a-s) were confirmed by IR, 1H NMR, 13C NMR, Fmass and chemical analysis. All above compounds were screened for their antimicrobial activity against some selected bacteria and fungi and for antituberculosis activity compounds have been screened against the bacterium M. tuberculosis.

scholarly journals SYNTHESIS AND PRELIMINARY PHARMACOLOGICAL EVALUATION OF NEW NAPROXEN ANALOGUES HAVING 1, 2, 4-TRIAZOLE-3-THIOL

2017 ◽  
Vol 9 (7) ◽  
pp. 66
Author(s):  
Monther F. Mahdi ◽  
Noor H. Naser ◽  
Nethal H. Hammud
Keyword(s):  
Aromatic Aldehydes ◽  
Heterocyclic Ring ◽  
Inflammatory Activity ◽  
Control Group ◽  
Paw Edema ◽  
Dose Equivalent ◽  
Edema Model ◽  
Anti Inflammatory ◽  
Derivatives Of

Objective: The objective of this search was to synthesize a new naproxen analogues having a 1,2,4-triazole-3-thiol heterocyclic ring, and preliminary pharmacological assessment of the anti-inflammatory activity of the synthesized compounds. Methods: The synthesis of naproxen analogues that having 1,2,4-triazole-3-thiol heterocyclic ring occur through esterification of naproxen, and then its reaction with hydrazine hydrate, and carbon disulfide, finally different aromatic aldehydes reacted with triazole derivatives of naproxen containing amino group to produce schiff bases.Results: In vivo acute anti-inflammatory activity of the synthesize compounds (Va-Vd) was evaluated in rats using egg-white induced edema model of inflammation in a dose equivalent to (50 mg/kg) of naproxen. All tested compounds were produced a significant reduction in paw edema with respect to the effect of propylene glycol 50% v/v (control group). Compound Vd produced superior anti-inflammatory activity compared to naproxen.Conclusion: The results obtained in this work give evidence about the valid synthesis of 1,2,4 triazole-3-thiol derivatives of naproxen, which reacted with different aldehydes to yield several schiff bases. The incorporation of benzaldehyde possess para-electron donating group (para-hydroxyl benzaldehyde) will increase the anti-inflammatory activity of naproxen.

scholarly journals Optical rotatory power. I—A theoretical calculation for a molecule containing only isotropic refractive centres

1934 ◽  
Vol 144 (853) ◽  
pp. 655-675 ◽  
Keyword(s):  
Theoretical Calculation ◽  
Optical Activity ◽  
Chemical Structure ◽  
Central Atom ◽  
Optical Rotation ◽  
Rotatory Power ◽  
Theoretical Formula ◽  
Optical Rotatory ◽  
Present Communication ◽  
Optical Rotatory Power

Ever since the time of van’t Hoff and Le Bel the number investigations dependent on optical activity, or attempting to elucidate optical activity, has been very great, and it is remarkable that, even at the present time, there is no theoretical formula which gives the relation between the magnitude of the rotation and the chemical structure of the molecule concerned. The present communication supplies this want with regard to the molecule of the simplest asymmetric type: the molecule with four different groups attached to one central atom. Various special hypothese have been postulated to explain optical activity, but a few investigators have shown quite definitely that there is no necessity for any of these hypotheses. Born* and Oseen have shown independently that, if the molecule has a dissymmetric structure, the ordinary refractive properties of the atoms will account for an optical rotation. Gray* and de Mallemann have attempted calculations of formulæ for optical retatory power on this basis. However, it has not been possible to condense the numerous algebraic terms which occur in these calculaations into a compact form.

Approaches to the Synthesis of 5-Benzylidene-2-imidazolin-4-ones

1990 ◽  
Vol 43 (2) ◽  
pp. 367 ◽  
Author(s):  
RH Prager ◽  
C Tsopelas
Keyword(s):  
Acetic Anhydride ◽  
Aromatic Aldehydes ◽  
Darzens Reaction ◽  
Derivatives Of

Aromatic aldehydes , but not ketones, can be condensed with glycocyamidine . The corresponding alkylbenzylideneglycocyamidines may be made from glycidic esters by reaction with guanidine, followed by cyclization with acetic anhydride. A number of mono- and di -acetylated derivatives of 6,7-dihydropyrrolo[2,3-c]azepine-4,8(1H,5H)- dione have been prepared, but failed to undergo the Darzens reaction. Bromo- and iodo-2-arylazoimidazoles, protected on nitrogen by the methoxyethoxymethyl group, failed to undergo clean lithiation.

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