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1.
Several amino acid ester hydrochlorides were reacted with ammonium formate to give N-formyl amino acid esters in good yields. 相似文献
2.
An efficient method for N-alkylation of diethyl acetamidomalonate (DEAM) is reported. C-Alkenylation was achieved by treating the N-alkenylated DEAM with various electrophiles in the presence of Cs2CO3. RCM reactions of C- and N-alkenylated products gave cyclic amino acid derivatives in good yields. 相似文献
3.
Kotha A Raman RC Ponrathnam S Kumar KK Shewale JG 《Applied biochemistry and biotechnology》1998,74(3):191-203
Various glycidyl methacrylate (GMA) copolymers were synthesized by suspension polymerization, using pentaerythritol triacrylate (PETA), trimethylolpropane triacrylate (TMPTA), and trimethylolpropane trimethacrylate (TRIM) as crosslinking comonomers. These copolymers were evaluated for the immobilization of penicillin G acylase. Broad pore-size distribution that was observed was in the range 5-300 nm. Both surface area and pore volume increased with increase in the mole fraction of crosslinking comonomer (increasing crosslink density). The pore volume of the copolymers was more than doubled by including lauryl alcohol as porogen. Binding of penicillin G acylase (PGA) was quantitative on highly crosslinked copolymers. The expression of bound PGA was better on the relatively more hydrophilic GMA-TMPTA and GMA-PETA copolymer supports compared to the GMA-TRIM copolymers. Among the different copolymers studied, GMA-TMPTA copolymer 7411 exhibited highest activity of immobilized penicillin G acylase (167.4 IU/g) with 35.1% expression. 相似文献
4.
Raghavendhar R. Kotha Fakir Shahidullah Tareq Devanand L. Luthria 《Molecules (Basel, Switzerland)》2022,27(15)
In this study, we evaluated the extractability of three curcuminoids (curcumin, demethoxycurcumin, and bisdemethoxycurcumin) from turmeric powder in several solvents using high-performance liquid chromatography (HPLC) with the diode-array detection method. These solvents include water, milk (homogenized, 2% reduced fat, low fat, fat free, soy, almond, coconut, and milkadamia), and aqueous ethanols (0%, 4%, 10%, 20%, 30%, 40%, 50%, and 100%). Ambient water was able to extract only 0.55 mg/g of curcuminoids, whereas warm water extracted more than four-fold higher amounts (2.42 mg/g). Almond, coconut, and milkadamia milk were able to extract only small amounts of curcuminoids at ambient temperatures (0.01–0.07 mg/g). The extractability of curcuminoids in these milk types did not improve, even in warm conditions (0.08–0.37 mg/g). Whereas dairy and soy milk extracted 6.76–9.75 mg/g of curcuminoids under ambient conditions, their extractability increased significantly in warm conditions by 30–100% higher (11.7–14.9 mg/g). The solubility of curcuminoids also varied remarkably in different proportions of aqueous-alcohol mixtures. With 4% ethanol, only 1.7 mg/g of curcuminoids were extracted, and the amounts improved with the increase in ethanol content up to 50% (32.2 mg/g), while 100% ethanol extracted a similar amount as 50% ethanol (34.2 mg/g). This study suggests that the extractability of curcuminoids from turmeric will be dependent on the type of diets consumed with the turmeric supplements. 相似文献
5.
C3-symmetric alkyloxy/aryloxy polyether dendrimers have been synthesized from 1,3,5-triphenylbenzene and 2,4,6-triphenyl-1,3,5-s-triazine and their liquid crystalline properties have been studied. C3-symmetric derivatives with n-hexyl and n-dodecyl chains at the periphery show mesophase properties when they are complexed with trinitrofluorenone at different temperatures. 相似文献
6.
Kandula Madhu Kumar Reddy Sarva Santhisudha Gundluru Mohan Kotha Peddanna Chippada Appa Rao 《Phosphorus, sulfur, and silicon and the related elements》2016,191(6):933-938
A one pot three-component nano Gd2O3 catalyzed neat reaction of 2-morpholinoethanamine and dimethylphosphite with various salicylaldehydes under microwave irradiation afforded a series of new α-aminophosphonates in high yields. The synthesized compounds were characterized by FT-IR, (1H, 13C, 31P)-NMR, and mass spectral methods. The antioxidant activity of these compounds was evaluated against DPPH, NO, and H2O2 methods and found that the compound Dimethyl (2-hydroxy-5-nitrophenyl) (2-morpholinoethylamino) methylphosphonate (4h) has higher antioxidant activity than the corresponding standards. 相似文献
7.
Madhu Kumar Reddy Kandula Mohan Gundluru Bakthavatchala Reddy Nemallapudi Sravya Gundala Peddanna Kotha Grigory V. Zyryanov Sridevi Chadive Suresh Reddy Cirandur 《Journal of heterocyclic chemistry》2021,58(1):172-181
A novel series of piperazine-1,2,3-triazole bearing dimethyl(((2-(4-((1H-1,2,3-triazole-4-yl)methyl)piperazin-1-yl)ethylamino)(2-hydroxyaryl)methyl)phosphonate derivatives have been prepared via copper-catalyzed azide-alkyne 1,3-dipolar cycloaddition (CuAAC) (Click Reaction) and Schiff base reactions. The synthesized compounds were confirmed by spectral characterization (1H, 13C and 31P NMR, and mass). The title compounds were evaluated for in vitro alpha glucosidase enzyme inhibition and in vitro antioxidant activity using DPPH and H2O2 methods. 相似文献
8.
Nazar Mohammed Gabra Bakheit Mustafa Yata Praveen Kumar C. Shobha Devi A. Srishailam P. Venkat Reddy Kotha Laxma Reddy S. Satyanarayana 《Journal of fluorescence》2014,24(1):169-181
A new ligand 3-(1H-imidazo[4,5-f][1,10]phenanthrolin-2yl)phenylboronic acid and its (IPPBA) three ruthenium(II) complexes [Ru(phen)2(IPPBA)](ClO4)2 (1), [Ru(bpy)2(IPPBA)](ClO4)2 (2) and [Ru(dmb)2(IPPBA)](ClO4)2 (3) have been synthesized and characterized by elemental analysis, UV/VIS, IR, 1H-NMR,13C-NMR and mass spectra. The binding behaviors of the three complexes to calf thymus DNA were investigated by absorption spectra, emission spectroscopy, viscosity measurements, thermal denaturation and photoactivated cleavage. The DNA-binding constants for complexes 1, 2 and 3 have been determined to be 7.9?×?105 M?1, 6.7?×?105 M?1 and 2.9?×?105 M?1. The results suggest that these complexes bound to double-stranded DNA in an intercalation mode. Upon irradiation at 365 nm, three ruthenium complexes were found to promote the cleavage of plasmid pBR322 DNA from super coiled form ? to nicked form ??. Further in the presence of Co2+, the emission of DNA–Ru(ΙΙ) complexes can be quenched. And when EDTA was added, the emission was recovered. The experimental results show that all three complexes exhibited the “on–off–on” properties of molecular “light switch”. The highest Cytotoxicity potential of the complex1 was observed on the Human alveolar adenocarcinoma (A549) cell line. Good agreement was generally found between the spectroscopic techniques and molecular docked model which provides further evidence of groove binding. 相似文献
9.
Sambasivarao Kotha Vittal Seema Kuldeep Singh Kodand Dinkar Deodhar 《Tetrahedron letters》2010,51(17):2301-421
Highly functionalized cage compounds have been prepared via cross-metathesis (CM) using Grubbs modified N-tolyl catalyst 7. A strategic utilization of photo-thermal metathesis and catalytic metathesis sequence for the synthesis of functionalized caged molecules has been demonstrated. 相似文献
10.
Formation of three diasteroisomeric spirodilactones 14a-c and 11 has been reported from diester 13 and 9, respectively, under the influence of mineral acid. 相似文献