156947-99-8Relevant articles and documents
VINYL ETHER HYDROLYSIS. 30. EFFECT OF β-CARBOXY AND β-CARBOMETHOXY SUBSTITUTION
Kresge, A. J.,Ubysz, D.
, p. 316 - 322 (1994)
Rates of hydrolysis of the vinyl ether functional groups of (Z)- and (E)-β-methoxyacrylic acid and (Z)- and (E)-β-methoxymethacrylic acid and their methyl esters were measured in aqueous perchloric acid solution.Additional rate measurements were also made for one substrate, (Z)-β-methoxymethacrylic acid, in buffer solutions down to pH 7, and a rate profile was constructed.The results show that the β-carboxy and β-carbomethoxy substituents produce strong rate retardations, ranging from 2000- to 25 000-fold, for both Z- and E-isomers in both the acrylic and methacrylic acid series.The rate profile for (Z)-β-methoxymethacrylic acid indicates that ionization of this substrate to the carboxylate ion form raises the rate of hydrolysis by a factor of 240.It is argued that this difference in reactivity of ionized and non-ionized forms of the substrate is due to conjugative and inductive effects of the substituents, rather than β-lactone formation as suggested in an earlier observation of the same phenomenon in a different system.
PANTETHEINE DERIVATIVES AND USES THEREOF
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Paragraph 2121, (2020/06/19)
The present disclosure relates to compounds of Formula (I), (II), or (II'): (I), (II), (II'), and pharmaceutically acceptable salts or solvates thereof. The present disclosure also relates to pharmaceutical compositions comprising the compounds and therapeutic and diagnostic uses of the compounds and pharmaceutical compositions.
Total Synthesis of Ajudazol A by a Modular Oxazole Diversification Strategy
Essig, Sebastian,G?lz, Jan Philipp,Menche, Dirk,Von Schwarzenberg, Karin,Wollnitzke, Philipp
supporting information, (2020/09/02)
The total synthesis of the potent respiratory chain inhibitor ajudazol A was accomplished by a concise strategy in 17 steps (longest linear sequence). The modular approach was based on a direct oxazole functionalization strategy involving a halogen dance
Iridium-catalyzed asymmetric hydrogenation of vinyl ethers
Zhu, Ye,Burgess, Kevin
supporting information; experimental part, p. 979 - 983 (2009/05/30)
A carbene-oxazoline catalyst 1 proved to be an effective catalyst for reduction of an enol ether that the literature suggested could not be hydrogenated effectively by P,N-Ir catalysts. Thus, a series of ester and alcohol substrates were hydrogenated using catalyst 1. Good to excellent enantioselectivities and high conversions were obtained.
