88718-12-1Relevant academic research and scientific papers
O-Benzylation of Carboxylic Acids Using 2,4,6-Tris(benzyloxy)-1,3,5-triazine (TriBOT) under Acidic or Thermal Conditions
Yamada, Kohei,Yoshida, Saki,Fujita, Hikaru,Kitamura, Masanori,Kunishima, Munetaka
, p. 7997 - 8002 (2015/12/24)
Two methods for the synthesis of benzyl esters from carboxylic acids using the O-benzylating reagent 2,4,6-tris(benzyloxy)-1,3,5-triazine (TriBOT) have been developed. The reactions were conducted either in the presence of a catalytic amount of TfOH at room temperature (acidic conditions) or in the absence of TfOH at 180-230 C (thermal conditions). Interestingly, the O-benzylation of hydroxy carboxylic acids under the two conditions afforded different products: The dibenzylated product under acidic conditions and the hydroxy ester under thermal conditions. In addition to these results, other evidence indicated that the former reaction proceeds through an SN1-type mechanism, and the latter by an SN2-type mechanism. Two methods for the O-benzylation of carboxylic acids using TriBOT have been developed under either acidic or thermal conditions. The O-benzylation of hydroxy carboxylic acids afforded the dibenzylated product under acidic conditions and the hydroxy ester under thermal conditions. The former reaction proceeds through an SN1-type mechanism and the latter by an SN2-type mechanism.
Synthesis of (S)-gizzerosine, a potent inducer of gizzard erosion in chicks
Shimasaki, Yasuharu,Kiyota, Hiromasa,Sato, Minoru,Kuwahara, Shigefumi
, p. 9628 - 9634 (2007/10/03)
(S)-Gizzerosine, a potent inducer of gizzard erosion in chicks, was synthesized using successive zinc-mediated and palladium-catalyzed coupling reactions as the key steps.
A novel 1-tert-butoxy-2-tert-butoxycarbonyl-1,2-dihydroisoquinoline (BBDI)-catalyzed esterification of N-protected amino acids with nearly equimolar amounts of alcohols in the presence of Boc2O
Saito, Yukako,Watanabe, Tomokazu,Takahata, Hiroki
, p. 3099 - 3102 (2007/10/03)
A very mild, BBDI-catalyzed esterification using approximately equimolar amounts of N-protected amino acids and alcohols, in junction with Boc2O is described.
Simple and mild esterification of N-protected amino acids with nearly equimolar amounts of alcohols using 1-tert-butoxy-2-tert-butoxycarbonyl-1,2- dihydroisoquinoline
Saito, Yukako,Yamaki, Toru,Kohashi, Fumiaki,Watanabe, Tomokazu,Ouchi, Hidekazu,Takahata, Hiroki
, p. 1277 - 1279 (2007/10/03)
A very mild, one-step esterification using nearly equimolar amounts of N-protected amino acids and alcohols, in conjunction with 1-tert-butoxy-2-tert- butoxycarbonyl-1,2-dihydroisoquinoline (BBDI) as a novel condensing reagent is described.
Broadening of the substrate tolerance of α-chymotrypsin by using the carbamoylmethyl ester as an acyl donor in kinetically controlled peptide synthesis
Miyazawa, Toshifumi,Tanaka, Kayoko,Ensatsu, Eiichi,Yanagihara, Ryoji,Yamada, Takashi
, p. 87 - 93 (2007/10/03)
In the kinetically controlled approach of peptide synthesis mediated by α-chymotrypsin, the broadening of the protease's substrate tolerance is achieved by switching the acyl donor from the conventional methyl ester to the carbamoylmethyl ester. Thus, as a typical example, the extremely low coupling efficiency obtained by employing the methyl ester of an inherently poor amino acid substrate, Ala, is significantly improved by the use of this particular ester. Its ameliorating effect is observed also in the couplings of other amino acid residues such as Gly and Ser as carboxy components.
Highly reactive, water soluble carbodiimides, intermediates and derivatives thereof
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, (2008/06/13)
Novel water soluble carbodiimides, and intermediates or derivatives thereof, such as isoureas or isothioureas, are described. A particularly preferred embodiment is bis[4-(2,2-dimethyl-1,3-dioxolyl)methyl] carbodiimide (BDDC), which can be synthesized efficiently from 1,2-isopropylideneglycerol (solketal). The isoureas are effective esterifying agents. The corresponding N-protected amino acid tert-butyl, benzyl, isopropyl, ethyl, and methyl esters can be synthesized in high yield under neutral conditions, with no urea residue after simply washing with aqueous acid. Amino acid couplings utilizing carbodiimide embodiments give peptides in good yield, free of carbodiimide by-products, after washing with dilute acid, while racemization-free peptides are also obtained.
Applications of Radical Addition Reactions to the Synthesis of a C-Glucoside and a Functionalised Amino-acid
Adlington, Robert M.,Baldwin, Jack E.,Basak, Amit,Kozyrod, Robert P.
, p. 944 - 945 (2007/10/02)
Addition of carbon radicals derived from tetra-acetylglucosyl and β-alanyl derivatives to acrylic acid or esters provides a short route to a C-glucoside and a functionalised α-amino-acid, respectively.
