949-13-3Relevant academic research and scientific papers
Mesoporous aromatic frameworks modified by metal chlorides in phenol alkylation with oct-1-ene
Talanova, M. Yu.,Guojun,Karakhanov,Anisimov
, p. 2083 - 2087 (2020/01/21)
Mesoporous polyaromatic frameworks (PAF) based on tetraphenylmethane were synthesized. The PAF/AlCl3 and PAF/FeCl3 catalysts were prepared by impregnating the synthesized products with aluminum and iron chlorides, respectively. The r
Covalent modification of cyclooxygenase-2 (COX-2) by 2-acetoxyphenyl alkyl sulfides, a new class of selective COX-2 inactivators
Kalgutkar, Amit S.,Kozak, Kevin R.,Crews, Brenda C.,Hochgesang Jr., G. Phillip,Marnett, Lawrence J.
, p. 4800 - 4818 (2007/10/03)
All of the selective COX-2 inhibitors described to date inhibit the isoform by binding tightly but noncovalently at the substrate binding site. Recently, we reported the first account of selective covalent modification of COX-2 by a novel inactivator, 2-acetoxyphenyl hept-2-ynyl sulfide (70) (Science 1998, 280, 1268-1270). Compound 70 selectively inactivates COX-2 by acetylating the same serine residue that aspirin acetylates. This paper describes the extensive structure-activity relationship (SAR) studies on the initial lead compound 2-acetoxyphenyl methyl sulfide (36) that led to the discovery of 70. Extension of the S-alkyl chain in 36 with higher alkyl homologues led to significant increases in inhibitory potency. The heptyl chain in 2-acetoxyphenyl heptyl sulfide (46) was optimum for COX-2 inhibitory potency, and introduction of a triple bond in the heptyl chain (compound 70) led to further increments in potency and selectivity. The alkynyl analogues were more potent and selective COX-2 inhibitors than the corresponding alkyl homologues. Sulfides were more potent and selective COX-2 inhibitors than the corresponding sulfoxides or sulfones or other heteroatom-containing compounds. In addition to inhibiting purified COX-2, 36, 46, and 70 also inhibited COX-2 activity in murine macrophages. Analogue 36 which displayed moderate potency and selectivity against purified human COX-2 was a potent inhibitor of COX-2 activity in the mouse macrophages. Tryptic digestion and peptide mapping of COX-2 reacted with [1-14C-acetyl]-36 indicated that selective COX-2 inhibition by 36 also resulted in the acetylation of Ser516. That COX-2 inhibition by aspirin resulted from the acetylation of Ser516 was confirmed by tryptic digestion and peptide mapping of COX-2 labeled with [1- 14C-acetyl]salicyclic acid. The efficacy of the sulfides in inhibiting COX- 2 activity in inflammatory cells, our recent results on the selectivity of 70 in attenuating growth of COX-2-expressing colon cancer cells, and its selectivity for inhibition of COX-2 over COX-1 in vivo indicate that this novel class of covalent modifiers may serve as potential therapeutic agents in inflammatory and proliferative disorders.
Metal cation-exchanged montmorillonite (Mn+-mont)-catalysed aromatic alkylation with aldehydes and ketones
Tateiwa, Jun-Ichi,Hayama, Ei,Nishimura, Takahiro,Uemura, Sakae
, p. 1923 - 1928 (2007/10/03)
The alkylation of aromatic compounds with aldehydes and ketones in the presence of a variety of metal cation-exchanged montmorillonites (Mn+-mont; Mn+ = Zr4+, Al3+, Fe3+, Zn2+, H+, Na+) has been investigated. Al3+- and Zr4+-Monts are revealed to be effective as catalysts, while no reaction takes place with Na+-mont. Al3+-Mont-catalysed alkylation of phenol with several aldehydes produces mainly or almost solely the corresponding gem-bis(hydroxyphenyl)alkanes (bisphenols) in good yields, while that with several ketones affords selectively the corresponding alkylphenols in moderate to good yields. The alkylation always occurs at the carbonyl carbon without any skeletal rearrangement and the kind of products depends much on the steric hindrance of an electrophilic intermediary carbocation. The alkylation of anisole, veratrole and p-cresol proceeds well, while that of toluene, benzene, chlorobenzene and nitrobenzene scarcely occurs.
Al3+-exchanged montmorillonite as an effective solid catalyst for selective synthesis of alkylphenols and bisphenols
Tateiwa, Jun-Ichi,Hayama, Ei,Nishimura, Takahiro,Uemura, Sakae
, p. 59 - 60 (2007/10/03)
Al3+-Exchanged montmorillonite-catalyzed aromatic alkylation of phenol with aldehydes produces the corresponding bisphenols mainly or almost solely in good yields, while that with ketones affords selectively the corresponding alkylphenols in mo
Catalysts for alkoxylation reactions
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, (2008/06/13)
Catalysts producing a sharply peaked alkoxylation distribution during the alkoxylation of organic materials comprise mixtures of BF3 and metal alkyls or metal alkoxides, SiF4 and metal alkyls or metal alkoxides, or mixtures of these catalysts.
Methods of alkoxylation
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, (2008/06/13)
Catalysts comprising mixtures of HF and metal alkoxides and mixed metal alkoxides produce a sharply peaked alkoxylation distribution during the alkoxylation of organic materials.
Catalysts for alkoxylation reactions
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, (2008/06/13)
Catalysts and a method of using said catalysts for the alkoxylation of a variety of materials is disclosed. Catalysts so described produce alkoxylates having a very sharp alkoxylate distribution. The catalysts are supported and unsupported dialkoxy and dialkyl metal fluorides and halides and alkyl metal difluorides and dihalides.
Herbicidal 1,2,4-oxadiazin-5-one compositions
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, (2008/06/13)
Herbicidal and/or phyto-hormonal compositions containing 1,2,4-oxadiazin-5-one of the formula STR1 WHERE R represents H, alkyl or phenyl and Ar represents substituted phenyl or a 5 membered aromatic heterocyclic radical with O, S or N as the hetero-atom and optionally substituted are described.
