13683-89-1Relevant articles and documents
Pictet-Spengler condensations using 4-(2-aminoethyl)coumarins
Sviripa, Vitaliy M.,Fiandalo, Michael V.,Begley, Kristin L.,Wyrebek, Przemyslaw,Kril, Liliia M.,Balia, Andrii G.,Parkin, Sean R.,Subramanian, Vivekanandan,Chen, Xi,Williams, Alexander H.,Zhan, Chang-Guo,Liu, Chunming,Mohler, James L.,Watt, David S.
, p. 13415 - 13429 (2020/08/28)
Androgen-deprivation therapy (ADT) is only a palliative measure, and prostate cancer invariably recurs in a lethal, castration-resistant form (CRPC). Prostate cancer resists ADT by metabolizing weak, adrenal androgens to growth-promoting 5α-dihydrotestosterone (DHT), the preferred ligand for the androgen receptor (AR). Developing small-molecule inhibitors for the final steps in androgen metabolic pathways that utilize 17-oxidoreductases required probes that possess fluorescent groups at C-3 and intact, naturally occurring functionality at C-17. Application of the Pictet-Spengler condensation to substituted 4-(2-aminoethyl)coumarins and 5α-androstane-3-ones furnished spirocyclic, fluorescent androgens at the desired C-3 position. Condensations required the presence of activating C-7 amino or N,N-dialkylamino groups in the 4-(2-aminoethyl)coumarin component of these condensation reactions. Successful Pictet-Spengler condensation, for example, of DHT with 9-(2-aminoethyl)-2,3,6,7-tetrahydro-1H,5H,11H-pyrano[2,3-f]pyrido[3,2,1-ij]quinolin-11-one led to a spirocyclic androgen, (3R,5S,10S,13S,17S)-17-hydroxy-10,13-dimethyl-1,2,2′,3′,4,5,6,7,8,8′,9,9′,10,11,12,12′,13,13′,14,15,16,17-docosahydro-7′H,11′H-spiro-[cyclopenta[a]phenanthrene-3,4′-pyrido[3,2,1-ij]pyrido[4′,3′:4,5]pyrano[2,3-f]quinolin]-5′(1′H)-one. Computational modeling supported the surrogacy of the C-3 fluorescent DHT analog as a tool to study 17-oxidoreductases for intracrine, androgen metabolism. This journal is
Coumarin-containing photo-responsive nanocomposites for NIR light-triggered controlled drug release via a two-photon process
Ji, Weidong,Li, Najun,Chen, Dongyun,Qi, Xiuxiu,Sha, Wenwei,Jiao, Yang,Xu, Qingfeng,Lu, Jianmei
supporting information, p. 5942 - 5949 (2013/11/19)
A new multifunctional nanovehicle for tumor therapy and cell imaging was fabricated by coating NIR light-responsive polymers (HAMAFA-b-DDACMM) onto the surface of octadecyltrimethoxysilane (C18)-modified hollow mesoporous silica nanoparticles (HMS@C18) via self-assembly. First, the targeting NIR light-responsive block copolymer was synthesized by the RAFT living polymerization of [7-(didodecylamino) coumarin-4-yl] methyl methacrylate with hydroxyethylacrylate and N-(3-aminopropyl) methacrylamide hydrochloride and then grafted with folic acid (FA). The copolymers could be disrupted by excitation by a femtosecond NIR light laser (800 nm) via a two-photon absorption process due to the high two-photon absorption cross-section of the coumarin moiety. In order to enhance the drug loading capacity and biological stability of the nanovehicle, HMS nanoparticles modified by hydrophobic octadecyl chains were selected as the "core", which had a considerable drug loading efficiency of more than 70%. Then the core-shell nanocomposites (HMS@C18@HAMAFA-b-DDACMM) were obtained by coating the amphiphilic copolymers onto the core via self-assembly. Under excitation by NIR light at 800 nm, the pre-loaded drugs could be released from the nanocomposites due to the degradation of the light-responsive copolymers and the release efficiency was correlated with the irradiation time and light power. The in vitro experiments indicated that the nanocomposites were easily targeted into the tumor cells that over-expressed folic acid receptor (FR(+)) such as KB cells by endocytosis. Furthermore, the copolymer itself had strong fluorescence, which could be used to track the process of drug delivery.
CARBONYLATIVE REDUCTION OF NITROPHENOLS TO AMINOPHENOLS
Macho, Vendelin,Kucera, Milan,Kralik, Milan
, p. 514 - 520 (2007/10/02)
Two- or three-component catalysts composed of (i) sulfur or sulfur compound (H2S, CS2, COS, Na2S), (ii) basic additive (triethylamine, CH3ONa, Na2S), and usually (iii) vanadium(V) compounds (e.g.NH4VO3) were found to catalyze efficiently the reaction of CO + H2O with isomeric nitrophenols to give the corresponding aminophenols.The reaction proceeds smoothly at 398 and 483 K and initial pressure of 7 MPa, and its rate increases from 2- to 4-nitrophenol.The selectivity to aminophenols exceeding 96 per cent was obtained at the water to nitrophenol molar ratio higher than 5.The solvents such as methanol and dioxane ensured better contact of the reactants, which was necessary for achievement of such a high selectivity.The effectiveness of the sulfur components (based on the S content) is expressed by the following sequence: S : CS2 : Na2S : H2S : COS = 1 : 1.2 : 2.5 : 10 : 11.The reaction takes place also under the reduced CO pressure to 0.1 - 0.35 MPa.Formation of side products and mechanism of the reaction are discussed.