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161.
Shahida Parveen Kelvin K. H. Tong Muhammad KhawarRauf Mario Kubanik Muhammad Ashraf Shaheen Tilo Shnel Stephen M. F. Jamieson Muhammad Hanif Christian G. Hartinger 《化学:亚洲杂志》2019,14(8):1262-1270
Benzoylthiourea derivatives feature several donor atoms capable of coordinating to metal centers. We report here a series of Ru(η6‐p‐cymene) complexes employing benzoylthiourea derivatives as ligands. Such ligands often coordinate to metal centers through their S and O donor atoms. We isolated complexes where the ligands were mono‐ or bidentately coordinated to Ru involving the S donor atom and surprisingly in bidentate coordination mode a deprotonated thiourea nitrogen resulting in a 4‐membered ring structure around the metal center. DFT calculations were used to explain the differences in coordination behavior. These were complemented by stability studies and biological investigations of the compounds as anticancer agents. Several of the synthesized derivatives exhibited significant cell growth inhibitory activity, with the complexes featuring bidentate ligands being more potent than their monodentate counterparts. This can be explained by the higher stability of the former under the conditions employed in cell culture assays. 相似文献
162.
Farzana Kouser Vijay Kumar Sharma Masood Rizvi Shaista Sultan Neha Chalotra Vivek K. Gupta Utpal Nandi Bhahwal Ali Shah 《Tetrahedron letters》2018,59(22):2161-2166
A visible light mediated radical addition of thiophenols on 4-phenylbut-3-enoic acids to give diastereoselective synthesis of 3,4-disubstituted γ-lactones is reported. The reaction precludes the conventional prerequisite of conjugate addition. Furthermore, the lactones were successfully utilized in the synthesis of γ-ketoamides. 相似文献
163.
Sonogashira cross coupling is a well-known reaction for the formation of carbon–carbon bond. It involves the coupling of aryl halides with terminal alkynes to synthesize versatile functionalized alkyne scaffolds having diverse applications. Many of the natural products and important pharmaceutical drugs can be obtained through this reaction. In this regard, hectic progress has been put by the synthetic chemists to make this cross coupling more effective. This review article discloses mild and environmental friendly reaction conditions of Sonogashira cross coupling developed during 2013–2018. 相似文献
164.
Manmeet Singh Manhas Parveen Kumar Athar A. Hashmi Zaheer Khan 《Kinetics and Catalysis》2009,50(1):82-87
The kinetics and mechanism of the oxidation of D-galactose by chromium(VI) in the absence and presence of cerium(IV) and manganese(II) were studied spectrophotometrically
in aqueous perchloric acid media. The reaction is first order in both [D-galactose] and [H+]. The cerium(IV) inhibits the oxidation path, whereas manganese(II) catalyzes the reactions. The observed inhibitory role
of cerium(IV) suggests the formation of chromium(IV) as an intermediate. In the manganese(II) catalyzed path, the D-galactose-manganese(II) complex was considered to be an active oxidant. In this path, the complex forms a ternary chromate
ester with chromium(IV) which subsequently undergoes acid catalyzed redox decomposition (one-step three-electron transfer:
Indian J. Chem., 2004, vol. 42A, p. 1060; Colloids and Surfaces, 2001, vol. 193, p. 1) in the rate determining step. On the basis of kinetic data, the mechanism of D-galactose oxidation is proposed for parent, the manganese(II) catalyzed and cerium(IV) — inhibited reactions. The activation
parameters E
a = 59 kJ ΔH
# = 57 kJ mol−1, and ΔS
# = −119 J K−1 mol−1 are calculated and discussed. Reaction products are also examined.
Published in Russian in Kinetika i Kataliz, 2009, Vol. 50, No. 1, pp. 90–95.
This article was submitted by the authors in English. 相似文献
165.
166.
Supramolecular Gels by Design: Towards the Development of Topical Gels for Self‐Delivery Application
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Rumana Parveen Prof. Dr. Parthasarathi Dastidar 《Chemistry (Weinheim an der Bergstrasse, Germany)》2016,22(27):9257-9266
Following a supramolecular synthon approach, simple salt formation has been employed to gain access to a series of supramolecular gelators derived from the well‐known non‐steroidal anti‐inflammatory drug (NSAID) ibuprofen. A well‐studied gel‐inducing supramolecular synthon, namely primary ammonium monocarboxylate (PAM), has been exploited to generate a series of PAM salts by reacting ibuprofen with various primary amines. Remarkably, all of the salts ( S1 – S7 ) thus synthesized proved to be good to moderate gelators of various polar and nonpolar solvents. Single‐crystal and powder X‐ray diffraction studies established the existence of the PAM synthons in the gel network, confirming the efficacy of the supramolecular synthon approach employed. Most importantly, the majority of the salts ( S2 , S3 , S6 , and S7 ) were capable of gelling methyl salicylate (MS), an important ingredient found in many commercial topical gels. In vitro experiments (MTT and PGE2 assays) revealed that all of the salts (except S3 and S7 ) were biocompatible (up to 0.5 mm concentration), and the most suited one, S6 , displayed anti‐inflammatory ability as good as that of the parent drug ibuprofen. A topical gel of S6 with methyl salicylate and menthol was found to be suitable for delivering the gelator drug in a self‐delivery fashion in treating skin inflammation in mice. Histological studies, including immunohistology, were performed to further probe the role of the gelator drug S6 in treating inflammation. Cell imaging studies supported cellular uptake of the gelator drug in such biomedical application. 相似文献
167.
168.
Mehtab Parveen Akhtar Ali Ali Mohammed Malla Pedro Sidónio Pereira Silva Manuela Ramos Silva 《Chemical Papers》2011,65(5):735-738
Petroleum ether-benzene extract of the leaves of Ficus krishnae afforded a novel halogenated 2H-chromen-2-one named 3-chloro-7-methoxy-4-methyl-chromen-2-one. Its structure was established on basis of chemical and physical
evidence (IR, 1H NMR, and MS data) as well as on X-ray crystallographic studies. 相似文献
169.
Tariq Mohammad Iqbal Zeenat Ali Javed Baboota Sanjula Parveen Rabea Mirza Mohd. Aamir Ahmad Sayeed Sahni Jasjeet Kaur 《平面色谱法杂志一现代薄层色谱法》2014,27(2):124-131
JPC – Journal of Planar Chromatography – Modern TLC - A simple, sensitive, precise, rapid, and reliable high-performance thin-layer chromatographic (HPTLC) method for the simultaneous... 相似文献
170.
Md. Harun-Ur-Rashid Hironori Iwasaki Shahanaz Parveen Shigeki Oogai Masakazu Fukuta Md. Amzad Hossain Toyoaki Anai Hirosuke Oku 《Applied biochemistry and biotechnology》2018,186(3):613-632
In higher plants, multiple copies of the cysteine synthase gene are present for cysteine biosynthesis. Some of these genes also have the potential to produce various kinds of β-substitute alanine. In the present study, we cloned a 1275-bp cDNA for cytosolic O-acetylserine(thiol)lyase (cysteine synthase) (Cy-OASTL) from Leucaena leucocephala. The purified protein product showed a dual function of cysteine and mimosine synthesis. Kinetics studies showed pH optima of 7.5 and 8.0, while temperature optima of 40 and 35 °C, respectively, for cysteine and mimosine synthesis. The kinetic parameters such as apparent Km, kcat were determined for both cysteine and mimosine synthesis with substrates O-acetylserine (OAS) and Na2S or 3-hydroxy-4-pyridone (3H4P). From the in vitro results with the common substrate OAS, the apparent kcat for Cys production is over sixfold higher than mimosine synthesis and the apparent Km is 3.7 times lower, suggesting Cys synthesis is the favored pathway. 相似文献