17157-48-1Relevant academic research and scientific papers
The Energy Surface for Isomeric (1+) Ions: Further Experimental Evidence
Turecek, Frantisek,McLafferty, F. W.
, p. 608 - 611 (1983)
Mass spectra from collisionally activated dissociation (CAD) of (1+) ions, including isotopically labeled analogs, provide further information on the isomers O(1+)> (a), (b), (c) and (d).Our data generally support the recent conclusions from theory by Radom and coworkers and from experiment by Terlouw, Holmes and coworkers.Most acetyl-containing molecular ions form a ions in high purity only at low energies, consistent with isomerization of higher energy molecular ions to form the more stable enol which dissociates to b.Isomer d, prepared from (ClCH2)2CHOH, undergoes facile hydrogen scrambling, presumably through a degenerate 1,2-hydrogen shift.Theory suggests that c undegoes spontaneous isomerization to a and d; although (1+) ions from BrCH2CHO appear to consist of a and ca.15percent d, the latter are formed without substantial hydrogen scrambling.
FTIR Spectroscopic Studies of the Mechanisms of the Halogen Atom Initiated Oxidation of Haloacetaldehydes
Chen, Junyi,Young, Valerie,Catoire, Valery,Niki, Hiromi
, p. 6580 - 6586 (1996)
Product studies of Cl atom initiated oxidation of ClCH2CHO and Br atom initiated oxidation of BrCH2CHO were conducted by FTIR spectroscopy at 297 +/- 2 K in 700 Torr of O2/N2 diluent, using reactant partial pressures in both the torr and militorr ranges.The halogen atoms initiate reaction via hydrogen abstraction from the aldehydic group (CHO), producing haloacetyl radicals, XCH2CO, where X = Cl or Br.In 700 Torr of air, the XCH2CO radicals may react via three channels: (i) O2-addition, XCH2CO + O2 -> XCH2C(O)O2; (ii) unimolecular dissociation by C-C bond cleavage, XCH2CO (+M) -> XCH2 + CO (+M); and (iii) unimolecular dissociation by C-X bond cleavage, XCH2CO (+M) -> X + CH2=C=O (+M).All three channels were observed for BrCH2CO radicals, enabling estimation of the branching ratios, but ClCH2CO reacts only by O2-addition.Subsequent reactions of XCH2C(O)O2 radicals lead to XCH2O radical and CO2 formation.The ClCH2O radical reacts with O2 to produce CHClO and HO2, while the BrCH2O radical mainly eliminates the Br atom, based on CH2O detected.
Preparation of new omega-aldehydoalkyl 1-thio-D-glycopyranosides, and their coupling to bovine serum albumin by reductive alkylation.
Lee,Lee
, p. 49 - 55 (1982)
Synthesis of two omega-aldehydoalkyl 1-thioglycosides of D-glucopyranose and of D-galactopyranose is described. 3-Oxopropyl and 2-oxoethyl 1-thioglycosides were prepared by treating a tetra-O-acetyl-1-thioaldose with either acrolein or 2-bromo-acetaldehyde, followed by O-deacetylation under mild conditions. These omega-aldehydoalkyl 1-thioglycosides were successfully attached to bovine serum albumin (BSA) by reductive alkylation as described previously. With the 3-oxopropyl 1-thioglycosides, much higher levels of sugar attachment (e.g., approximately 80 mol of sugar per mol of BSA) were attained than hitherto possible with any sugar derivative tested.
Synthesis of 2-unsubstituted 1,3-selenazoles by cyclization of selenoformamide with α-bromocarbonyl compounds
Below, Harald,Pfeiffer, Wolf-Diethard,Geisler, Karlheinz,Saghyan, Ashot S.,Fischer, Christine,Langer, Peter
, p. 592 - 596 (2015)
2-Unsubstituted 1,3-selenazoles were prepared by cyclization of selenoformamide with α-bromoacetophenones. Parent 1,3-selenazole was prepared by cyclization of selenoformamide with α-bromoacetaldehyde.
Kinetic study of the self-reactions of the BrCH2CH2O2 and BrCH(CH3CH(CH3O2 radicals between 275 and 373 K
Villenave, Eric,Moisan, Sandy,Lesclaux, Robert
, p. 2470 - 2477 (2003)
A conventional flash photolysis technique was used to measure the self-reaction rate constants of the primary BrCH2CH2O2 (2-bromoethylperoxy) and secondary BrCH(CH3)CH(CH3)O2 (2-bromo-l-methylpropylperoxy) β-brominated peroxy radicals, at temperatures in the range of 275-373 K. The absolute UV absorption spectra of BrCH2CH2O2 and BrCH(CH3)CH(CH3)O2 were also measured and compared to those obtained previously for these radicals. The temperature dependence of the self-reaction rate constants provided the following Arrhenius expressions: k(BrCH2CH2O2 + BrCH2CH2O2) = (6.15+5.152.99) × 10-14 exp{(1247 ± 203) K/T} cm3 molecule-1 s-1 and k(BrCH(CH3)CH(CH3)O2 + BrCH(CH3)CH(CH3)O2) = (7.60+22.05-5.65) × 10-15 exp{(1305 ± 428) K/T} cm3 molecule-1 s-1, where the uncertainties represent 95% confidence limits associated with the statistical fitting procedure and include the contribution for the expanded uncertainties in the individual rate constant. These results confirm the enhancement of the peroxy radical self-reaction reactivity upon β-substitution, which is similar for Br, Cl, or OH substituents. Structure-activity relationships are proposed for self-reactions of β-substituted peroxy radicals.
Iridium-catalyzed enantioselective allylic substitution with aqueous solutions of nucleophiles
Sandmeier, Tobias,Goetzke, F. Wieland,Krautwald, Simon,Carreira, Erick M.
, p. 12212 - 12218 (2019)
The iridium-catalyzed asymmetric allylic substitution under biphasic conditions is reported. This approach allows the use of various unstable and/or volatile nucleophiles including hydrazines, methylamine, t-butyl hydroperoxide, N-hydroxylamine, α-chloroacetaldehyde and glutaraldehyde. This transformation provides rapid access to a broad range of products from simple starting materials in good yields and up to >99% ee and 20:1 d.r. Additionally, these products can be elaborated efficiently into a diverse set of cyclic and acyclic compounds, bearing up to four stereocenters.
Synthesis of Ketones by C?H Functionalization of Aldehydes with Boronic Acids under Transition-Metal-Free Conditions
Roscales, Silvia,Csáky, Aurelio G.
supporting information, p. 8728 - 8732 (2021/03/16)
A method for the synthesis of ketones from aldehydes and boronic acids via a transition-metal-free C?H functionalization reaction is reported. The method employs nitrosobenzene as a reagent to drive the simultaneous activation of the boronic acid as a boronate and the activation of the C?H bond of the aldehyde as an iminium species that triggers the key C?C bond-forming step via an intramolecular migration from boron to carbon. These findings constitute a practical, scalable, and operationally straightforward method for the synthesis of ketones.
Stereoselective synthesis of (6Z,8E)-undeca-6,8,10-trien-3-one (yuzunone) for its characterization in yuzu and various citrus essential oils
Uehara, Ayaka,Baldovini, Nicolas
, (2020/10/02)
(6Z,8E)-Undeca-6,8,10-trien-3-one (yuzunone) is reported to be one of the main olfactory contributors of the specific fruity-green-balsamic odor of yuzu peel oil. Using an original stereoselective synthesis, we prepared a pure sample of yuzunone, which was used as a reference compound to check its presence by GC–MS and GC–O in 5 commercial samples of yuzu and citrus essential oils. Surprisingly, we could not detect yuzunone by GC–MS in any of our samples. However, it could be detected by a small part of the panelists involved in GC–O/AEDA experiments in a yuzu commercial oil, but its olfactory contribution proved to be very limited.
Scaffold-Hopping Strategy on a Series of Proteasome Inhibitors Led to a Preclinical Candidate for the Treatment of Visceral Leishmaniasis
Thomas, Michael,Brand, Stephen,De Rycker, Manu,Zuccotto, Fabio,Lukac, Iva,Dodd, Peter G.,Ko, Eun-Jung,Manthri, Sujatha,McGonagle, Kate,Osuna-Cabello, Maria,Riley, Jennifer,Pont, Caterina,Simeons, Frederick,Stojanovski, Laste,Thomas, John,Thompson, Stephen,Viayna, Elisabet,Fiandor, Jose M.,Martin, Julio,Wyatt, Paul G.,Miles, Timothy J.,Read, Kevin D.,Marco, Maria,Gilbert, Ian H.
supporting information, p. 5905 - 5930 (2021/06/01)
There is an urgent need for new treatments for visceral leishmaniasis (VL), a parasitic infection which impacts heavily large areas of East Africa, Asia, and South America. We previously reported on the discovery of GSK3494245/DDD01305143 (1) as a preclinical candidate for VL and, herein, we report on the medicinal chemistry program that led to its identification. A hit from a phenotypic screen was optimized to give a compound with in vivo efficacy, which was hampered by poor solubility and genotoxicity. The work on the original scaffold failed to lead to developable compounds, so an extensive scaffold-hopping exercise involving medicinal chemistry design, in silico profiling, and subsequent synthesis was utilized, leading to the preclinical candidate. The compound was shown to act via proteasome inhibition, and we report on the modeling of different scaffolds into a cryo-EM structure and the impact this has on our understanding of the series' structure-activity relationships.
Pd-Catalyzed Decarboxylative Olefination: Stereoselective Synthesis of Polysubstituted Butadienes and Macrocyclic P-glycoprotein Inhibitors
Chen, Xiangyang,Hao, Jiping,Houk, K. N.,Li, Yingzi,Lou, Liguang,Quan, Haitian,Song, Bichao,Wang, Lu,Xia, Yuanzhi,Xie, Peipei,Xu, Zhongliang,Yang, Weibo
supporting information, p. 9982 - 9992 (2020/06/27)
The efficient and stereoselective synthesis of polysubstituted butadienes, especially the multifunctional butadienes, represents a great challenge in organic synthesis. Herein, we wish to report a distinctive Pd(0) carbene-initiated decarboxylative olefination approach that enables the direct coupling of diazo esters with vinylethylene carbonates (VECs), vinyl oxazolidinones, or vinyl benzoxazinones to afford alcohol-, amine-, or aniline-containing 1,3-dienes in moderate to high yields and with excellent stereoselectivity. This protocol features operational simplicity, mild reaction conditions, a broad substrate scope, and gram-scalability. Notably, a structurally unique allylic Pd(II) intermediate was isolated and characterized. DFT calculation and control experiments demonstrated that a rare Pd(0) carbene intermediate could be involved in this reaction. Moreover, the polysubstituted butadienes as novel building blocks were unprecedentedly assembled into macrocycles, which efficiently inhibited the P-glycoprotein and dramatically reversed multidrug resistance in cancer cells by 190-fold.
