2768-18-5Relevant academic research and scientific papers
Sulfamyl Radicals Direct Photoredox-Mediated Giese Reactions at Unactivated C(3)-H Bonds
Kanegusuku, Anastasia L. G.,Castanheiro, Thomas,Ayer, Suraj K.,Roizen, Jennifer L.
, p. 6089 - 6095 (2019)
Alcohol-anchored sulfamate esters guide the alkylation of tertiary and secondary aliphatic C(3)-H bonds. The transformation proceeds directly from N-H bonds with a catalytic oxidant, a contrast to prior methods which have required preoxidation of the reactive nitrogen center, or employed stoichiometric amounts of strong oxidants to obtain the sulfamyl radical. These sulfamyl radicals template otherwise rare 1,6-hydrogen-atom transfer (HAT) processes via seven-membered ring transition states to enable C(3)-H functionalization during Giese reactions.
Benzoxazinones as PPARγ Agonists. 2. SAR of the Amide Substituent and In Vivo Results in a Type 2 Diabetes Model
Rybczynski, Philip J.,Zeck, Roxanne E.,Dudash Jr., Joseph,Combs, Donald W.,Burris, Thomas P.,Yang, Maria,Osborne, Melville C.,Chen, Xiaoli,Demarest, Keith T.
, p. 196 - 209 (2007/10/03)
A series of benzoxazinones has been synthesized and tested for PPARγ agonist activity. Synthetic approaches were developed to provide either racemic or chiral compounds. In vitro functional potency could be measured through induction of the aP2 gene, a target of PPARγ. These studies revealed that compounds with large aliphatic chains at the nitrogen of the benzoxazinone were the most potent. Substitution of the chain was tolerated and in many cases enhanced the in vitro potency of the compound. Select compounds were further tested for metabolic stability, oral bioavailability in rats, and efficacy in db/db mice after 11 days of dosing. In vivo analysis with 13 and 57 demonstrated that the series has potential for the treatment of type 2 diabetes.
Influence of bulky substituents on histamine H3 receptor agonist/antagonist properties
Sasse, Astrid,Ligneau, Xavier,Rouleau, Agnès,Elz, Sigurd,Ganellin, C. Robin,Arrang, Jean-Michel,Schwartz, Jean-Charles,Schunack, Walter,Stark, Holger
, p. 4000 - 4010 (2007/10/03)
Novel derivatives of 3-(1H-imidazol-4-yl)propanol were designed on the basis of lead compounds belonging to the carbamate or ether series possessing (partial) agonist properties on screening assays of the histamine H3 receptor. One pair of enantiomers in the series of α-methyl-branched chiral carbamates was stereoselectively prepared in high optical yields. Enantiomeric purity was checked by Mosher amide derivatives of precursors and capillary electrophoresis of the final compounds with trimethyl-β-cyclodextrin as chiral selector, and was determined to be ≥95%. The novel compounds were investigated in various histamine H3 receptor assays in vitro and in vivo. Some compounds displayed partial agonist activity on synaptosomes of rat brain cortex, whereas others exhibited antagonist properties only. Selected compounds were investigated in [125I]iodoproxyfan binding studies on the human histamine H3 receptor and showed high affinity in the nanomolar concentration range. Under in vivo conditions after oral administration to mice, some of the compounds exhibited partial or full agonist activity in the brain at low dosages. The (S)-enantiomer of one pair of chiral carbamates (9) proved to be the eutomer; thus, the (S)-enantiomer was selected for further pharmacological studies. In a peripheral in vivo test model in rats, measuring the level of inhibition of capsaicin-induced plasma extravasation, (S)-9 again proved its high oral agonist potency with full intrinsic activity (ED50 values of 0.07-0.1 mg/kg depending on tissue).
Assembly and disassembly of Langmuir-Blodgett films on poly[1- (trimethylsilyl)-1-propyne]: The uniqueness of calix[6]arene multilayers as permeation-selective membranes
Hendel, Robert A.,Nomura, Eisaku,Janout, Vaclav,Regen, Steven L.
, p. 6909 - 6918 (2007/10/03)
A series of calix[6]arene-based surfactants have been synthesized, which contain amide oxime head groups on their upper rim and 5,5-dimethylhexyl (I), n-octyl (II), n-dodecyl (III), and n-hexadecyl (IV) groups on their lower rim. Composite membranes that were fabricated from Langmuir-Blodgett (LB) multilayers derived from each surfactant plus poly[1-(trimethylsilyl)-1- propyne] (PTMSP) cast film showed a significant increase in their selectivity toward helium and nitrogen, relative to bare PTMSP. In sharp contrast, analogous composites that were prepared with LB multilayers of conventional single chain surfactants [arachidic acid (AA), cadmium arachidate (AA/Cd2+) and stearoamideoxime (SA)] exhibited permeation properties that were identical with those of bare PTMSP. When a polymeric surfactant [poly(1- octadecene-co-maleic anhydride), POM] is used for LB film construction, a modest increase in selectivity was observed. These findings, together with an analysis of representative composites by X-ray photoelectron spectroscopy, provide compelling evidence for the presence of intact, calix[6]arene-based LB assemblies on the surface of PTMSP; with the conventional single chain surfactants, however, disassembly and absorption into the bulk phase of the support is favored. The results of this study highlight the need for having individual surfactant molecules span individual pores on the surface of the support and strong intermolecular forces between neighboring surfactants to produce relatively defect-free LB films.
