856335-30-3Relevant academic research and scientific papers
Base- A nd Catalyst-Induced Orthogonal Site Selectivities in Acylation of Amphiphilic Diols
Ashush, Natali,Dobrovetsky, Roman,Fallek, Amit,Fallek, Reut,Portnoy, Moshe
supporting information, (2020/05/25)
Seeking to selectively functionalize natural and synthetic amphiphiles, we explored acylation of model amphiphilic diols. The use of a nucleophilic catalyst enabled a remarkable shift of the site selectivity from the polar site, preferred in background noncatalyzed or base-promoted reactions, to the apolar site. This tendency was significantly enhanced for organocatalysts comprising an imidazole active site surrounded by long/branched tails. An explanation of these orthogonal modes of selectivity is supported by competitive experiments with monoalcohol substrates.
Phosphorylation Organocatalysts Highly Active by Design
Dobrovetsky, Roman,Fallek, Amit,Kramer, Maria,Portnoy, Moshe,Weiss-Shtofman, Mor
supporting information, (2020/05/01)
The activity of nucleophilic organocatalysts for alcohol/phenol phosphorylation was enhanced through attaching oligoether appendages to a benzyl substituent on imidazole- or aminopyridine-based active units, presumably because of stabilizing n-cation interactions of the ethereal oxygens with the positively charged aza-heterocycle in the catalytic intermediates, and was substantially higher than that of known benchmark catalysts for a range of substrates. Density functional theory calculations and the study of analogues having a lower potential for such stabilizing interactions support our hypothesis.
Supramolecular phenoxy-alkyl maleate-based hydrogels and their enzyme/pH-responsive curcumin release
Kumar, Bijari Anil,Nayak, Rati Ranjan
, p. 5559 - 5567 (2019/04/04)
Low-molecular-weight gelators that self-assemble via non-covalent interactions have been attracting significant attention due to their good biocompatibility, low toxicity, inherent biodegradability as well as their convenience of design. Enzymatically dig
End-quenching of TiCl4-catalyzed quasiliving polyisobutylene with alkoxybenzenes for direct chain end functionalization
Morgan, David L.,Martinez-Castro, Nemesio,Storey, Robson F.
experimental part, p. 8724 - 8740 (2011/12/02)
Alkoxybenzenes were used to end-quench TiCl4-catalyzed quasiliving isobutylene polymerizations initiated from 2-chloro-2,2,4- trimethylpentane or 5-tert-butyl-1,3-di(1-chloro-1-methylethyl)benzene at -70 °C in 40/60 (v/v) hexane/methyl chloride. The alkoxybenzene/chain end molar ratios were in the range 2.5-4. Effective alkoxybenzene quenchers included those with simple alkyl groups, such as anisole and isopropoxybenzene, haloalkyl tethers, such as (3-bromopropoxy)benzene and (2-chloroethoxy)benzene, and even those with hydroxyl and amine functionality, such as 4-phenoxy-1-butanol and 6-phenoxyhexylamine. Alkylation was generally quantitative and occurred exclusively in the para position; multiple alkylations on the same alkoxybenzene were not observed. The alkylation reactions were tolerant of temperatures ranging from -70 to -30 °C and were unimpeded by the presence of endo- or exo-olefin termini. In situ cleavage of the ether linkage of anisole and isopropoxybenzene termini allowed single pot syntheses of phenol-terminated polyisobutylenes.
New N-(phenoxydecyl)phthalimide derivatives displaying potent inhibition activity towards α-glucosidase
Pascale, Rossana,Carocci, Alessia,Catalano, Alessia,Lentini, Giovanni,Spagnoletta, Anna,Cavalluzzi, Maria Maddalena,De Santis, Francesco,De Palma, Annalisa,Scalera, Vito,Franchini, Carlo
experimental part, p. 5903 - 5914 (2010/10/02)
Several members of a new family of non-sugar-type α-glucosidase inhibitors, bearing a phthalimide moiety connected to a variously substituted phenoxy ring by an alkyl chain, were synthesized and their activities were investigated. The efficacy of the inhibition activity appeared to be governed by the chain length of the substrate. Substrates possessing 10 carbons afforded the highest levels of activity, which were one to two orders of magnitude more potent than the known inhibitor 1-deoxynojirimycin (dNM). Furthermore, structure-activity relationship studies indicated a critical role of electron-withdrawing substituents at the phenoxy group for the activity. Derivatives bearing a chlorine atom along with a strong electron-withdrawing group, such as a nitro group, were the most potent of the series.
