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1.
Tapasi Chand Laxmikanta Khamari Deepak Chopra Saptarshi Mukherjee Manmohan Kapur 《Chemistry (Weinheim an der Bergstrasse, Germany)》2022,28(43):e202200723
A one-step Rh-catalyzed site-selective ortho-C−H alkynylation of perylene as well as naphthalene mono- and diimides is reported. A single step regioselective access to ortho-C−H alkynylated derivatives of these ryleneimides not only increases the step economy of the ortho-functionalization on these dyes but also provides a quick access route towards highly functionalized dyes that have potential optoelectronic applications. Increased solubility of tetra(triisopropylsilyl)acetylenyl PDIs in organic solvents greatly enhances their utility for further derivatization. 相似文献
2.
Upadhyay R. K. Bansal Rashmi R. Vajpai Usha 《Monatshefte für Chemie / Chemical Monthly》1976,107(5):1221-1225
Thin layer chromatographic behaviour of ten anils was studied on silica gel adsorbent mixed with starch binder with ten solvent systems. Simultaneous separation, identification and determination of ternary mixtures of isomers was stressed. TheR
F
increasing order was found to be dependent on the solvent and independent of the degree of saturation of the chamber. The correlations ofR
F
with max and (C=O) of isomers were established and used in their identification. Six anils were separated in methanol—benzene (11). 相似文献
3.
Lukman O. Alimi Mram Z. Alyami Santanu Chand Walaa Baslyman Niveen M. Khashab 《Chemical science》2021,12(7):2329
Biologics, such as functional proteins and nucleic acids, have recently dominated the drug market and comprise seven out of the top 10 best-selling drugs. Biologics are usually polar, heat sensitive, membrane impermeable and subject to enzymatic degradation and thus require systemic routes of administration and delivery. Coordination-based delivery vehicles, which include nanosized extended metal–organic frameworks (nMOFs) and discrete coordination cages, have gained a lot of attention because of their remarkable biocompatibility, in vivo stability, on-demand biodegradability, high encapsulation efficiency, easy surface modification and moderate synthetic conditions. Consequently, these systems have been extensively utilized as carriers of biomacromolecules for biomedical applications. This review summarizes the recent applications of nMOFs and coordination cages for protein, CRISPR–Cas9, DNA and RNA delivery. We also highlight the progress and challenges of coordination-based platforms as a promising approach towards clinical biomacromolecule delivery and discuss integral future research directions and applications.SACs can be efficiently used to load biologics such as proteins, CRISPR–Cas9, DNA and RNA and release them on-demand. 相似文献
4.
Substituted 6-ethoxyanilino-5H-benzo[a]phenothiazin-5-ones (3a-f) were synthesized by the cyclocondensation of 2-chloro-3-ethoxyanilino-1,4-naphthoquinones with zinc mercaptides of 2-aminothiophenol in pyridine. The nmr, ir and mass spectral data are presented and discussed. 相似文献
5.
A simple and accurate method has been developed for the determination of organoisothiocyanates and organoisocyanates based on their quantitative reaction with n-butylamine in dimethylformamide medium to form substituted thioureas and ureas, respectively. The solution is mixed with 6 to 7 times its volume of acetonitrile and an excess of carbon disulphide, which converts the residual amine quantitatively into the corresponding n-butylammonium n-butyl dithiocarbamate. The determination is completed by titrating the resulting dithiocarbamate with iodine monobromide solution in acetonitrile. The end point is detected visually by the yellow color imparted to the solution by the first drop of oxidant solution in excess. The dithiocarbamates are quantitatively oxidized to the corresponding thiuram disulphides. 相似文献
6.
The microgram detection and determination of picric acid with sodium hypochlorite solution is based on its oxidation in alkaline solution and chlorination with excess of chlorine present in hypochlorite solution. A characteristic orange color is obtained, which can be used as a specific test. The sensitivity of the picric acid was enhanced by performing the resin spot test. This color reaction was applied for the determination of picric acid spectrophotometrically. 相似文献
7.
Summary The adsorption studies of proteincationic, anionic and non-ionic surfactants and effect of electrolytes on the adsorption of triton 100 and protein mixture on kerosene oil/water interface have been studied. The lowering of interfacial tension is found to depend upon the emulsifier concentration and valency of the ions. 相似文献
8.
Bromine cyanide has been used for the potentiometric determination of sulphide, sulphite, thiocyanate, iodide, tin(II), arsenic(III),hydrazine hydrate, phenylhydrazine, 1,1-methylphenyldrazine and chloralhydrazine in glacial acetic acid and 1 : 1 acetic acid-acetic anhydride mixture, of thiourea, ethylthiourea, isopropylthiourea, benzylthiourea, alpha-phenylthiourea and o-tolythiourea in methanol, and of sodium methyl-, ethyl-,dimethyl-, diehtyl- and isopropyldithiocarbamates in ehtanol and acetonitrile media. The behaviour of bromine cyanide in these non- aqueous solvents has been compared with its behaviour in aqueous medium and with that of iodine cyanide in these non-aqueous solvents. 相似文献
9.
Alverson G Baker WF Ballocchi G Benson R Berg D Blusk S Bromberg C Brown D Carey D Chand T Chandlee C Choudhary BC Chung WH de Barbaro L DeSoi W Dlugosz W Dunlea J Easo S Engels E Faissler W Fanourakis G Ferbel T Garelick D Ginther G Glass G Glaubman M Gutierrez P Hartman K Huston J Johnstone C Kapoor V Kourbanis L Lanaro A Lirakis C Lobkowicz F Lukens P Mani S Maul A Mansour J Miller R Nelson CA Oh BY Orris D Pothier E Prebys E Rajaram BM Roser R Ruddick K Shepard P Shivpuri RK Sinanidis A 《Physical review D: Particles and fields》1993,48(1):5-28
10.
Michael additions of a β,γ-unsaturated ester and a nitrile to a variety of α,β-unsaturated ketones can be effected with high regioselectivity and in good yields using P(i-PrNCH2CH2)3N as a catalyst. 相似文献