62871-09-4Relevant articles and documents
Synthesis of indole analogues of the anti-Helicobacter pylori compounds CJ-13,015, CJ-13,102, CJ-13,104 and CJ-13,108
Wilson, Zoe E.,Heapy, Amanda M.,Brimble, Margaret A.
, p. 5379 - 5385 (2007)
Racemic syntheses of indole analogues of four phthalide-containing anti-Helicobacter pylori agents CJ-13,015, CJ-13,102, CJ-13,104 and CJ-13,108 are reported via manipulation of a common intermediate. This intermediate was formed by the N-alkylation of 4,6-dimethoxyindole with a long chain bromide followed by further chain extension. Oxidation, acetylation, or Barton-McCombie deoxygenation of the intermediate followed by Wacker oxidation afforded three analogues whilst further reduction of one analogue afforded the final analogue.
γ-pyrones from Gonystylus keithii, as new inhibitors of parathyroid hormone (PTH)-induced Ca release from neonatal mouse calvaria
Kanazawa, Tsutomu,Ohkawa, Yuki,Kuda, Takashi,Minobe, Yasushi,Tani, Tadato,Nishizawa, Makoto
, p. 1046 - 1051 (1997)
New γ-pyrones, 9'-oxopodopyrone (3) and 8-methyl-9'-oxopodopyrone (4) were isolated from the leaves of Gonystylus keithii, along with known γ- pyrones, 10'-oxopodopyrone (1) and 8-methyl-10'-oxopodopyrone (2). These γ- pyrones markedly inhibited the bovine parathyroid hormone (PTH)-induced Ca release from neonatal mouse calvaria in vitro. It is the first time that γ- pyrones showed inhibitory effects on bone resorption, and these compounds may be seed compounds of new drugs for osteoporosis.
Surface Perturbation of Vibrational Transitions of Pyrenesilanes Bound to Silica Gel
Hunnicutt, M. L.,Harris, J. M.,Lochmueller, C. H.
, p. 5246 - 5250 (1985)
Enhancement of weakly allowed vibrational transitions is reported for pyrenesilane molecules covalently bound to porous microparticulate silica.The appearance of these new bands is attributed to adsorptive interactions which alter the symmetry and electron density of the surface bound molecules.The intensity of the surface-perturbed vibrational modes is shown to vary as function of the bound silane surface concentration and the water content of the chemically modified silica.Thermal pretreatment of the modified silica produces large intensity differences indicating that the proton-donor properties of surface silanols are significantly influenced by the concentration of surface adsorbed water.Differences in the orientation and associative inetractions of bound and surface adsorbed molecules are also inferred.
Mechanical Properties of a Metal-Organic Framework formed by Covalent Cross-Linking of Metal-Organic Polyhedra
Lal, Garima,Derakhshandeh, Maziar,Akhtar, Farid,Spasyuk, Denis M.,Lin, Jian-Bin,Trifkovic, Milana,Shimizu, George K. H.
supporting information, p. 1045 - 1053 (2019/01/14)
Overcoming the brittleness of metal-organic frameworks (MOFs) is a challenge for industrial applications. To increase the mechanical strength, MOFs have been blended with polymers to form composites. However, this also brings challenges, such as integration and integrity of MOF in the composite, which can hamper the selectivity of gas separations. In this report, an "all MOF" material with mechanical flexibility has been prepared by covalent cross-linking of metal-organic polyhedra (MOPs). The ubiquitous Cu24 isophthalate MOP has been decorated with a long alkyl chain having terminal alkene functionalities so that MOPs can be cross-linked via olefin metathesis using Grubbs second generation catalyst. Different degrees of cross-linked MOP materials have been obtained by varying the amount of catalyst in the reaction. Rheology of these structures with varying number of cross-links was performed to assess the cross-link density and its homogeneity throughout the sample. The mechanical properties were further investigated by the nanoindentation method, which showed increasing hardness with higher cross-link density. Thus, this strategy of cross-linking MOPs with covalent flexible units allows us to create MOFs of increasing mechanical strength while retaining the MOP cavities.
Decarboxylative Olefination of Activated Aliphatic Acids Enabled by Dual Organophotoredox/Copper Catalysis
Tlahuext-Aca, Adrian,Candish, Lisa,Garza-Sanchez, R. Aleyda,Glorius, Frank
, p. 1715 - 1719 (2018/03/13)
Herein, we demonstrate a dual organophotoredox/copper catalytic strategy toward challenging decarboxylative olefination processes proceeding in high yields and selectivities. This operationally simple method uses photoactive organic molecules and Cu(II)-complexes as catalysts to provide rapid access to a wide variety of olefins from inexpensive synthetic and biomass-derived carboxylic acids under mild light-mediated conditions. Mechanistic investigations suggest that the reaction rate for this process is controlled solely by the incident photon flux.
