116733-45-0Relevant articles and documents
Nucleo-δ-peptides Derived from Conformationally Constrained Nucleo-δ-amino Acids: Preparation of Monomers
Karig, Gunter,Fuchs, Andreas,Buesing, Arne,Brandstetter, Tilmann,Scherer, Stefan,Rats, Jan W.,Eschenmoser, Albert,Quinkert, Gerhard
, p. 1049 - 1078 (2000)
Cyclic nucleo-δ-amino-acids that constitute monomers of a conformationally constrained nucleo-δ-peptide base-pairing system have been prepared. Their synthesis starts with an enantioselectively analyzed chirogenic Diels-Alder reaction, proceeds via a regioselective ε-iodolactamisation process, and ends with a regio- as well as stereoselective introduction of nucleobases through SN2-type opening of a transiently formed N-acylaziridine ring. Extensive use of X-ray crystal-structure analysis has been made to support structure assignments.
Asymmetric Diels-Alder Reactions of an Acrylic Acid Derivative Using a Chiral Titanium Catalyst
Narasaka, Koichi,Tanaka, Hiroko,Kanai, Fumihiko
, p. 387 - 391 (2007/10/02)
Asymmetric Diels-Alder reactions of an acrylic acid derivative using a catalytic amount of a chiral titanium reagent were performed with several dienes.The titanium catalyst was prepared by the alkoxy exchange between dichlorodiisopropoxytitanium(IV) and a chiral 1,4-diol derived from (2R,3R)-tartrate.By the use of the titanium catalyst, the reaction between 3-acryloyl-1,3-oxazolidin-2-one and dienes proceeded in a toluene-petroleum ether mixture in the presence of Molecular Sieves 4A to afford the Diels-Alder adducts in 72-100percent yields and 88 - >96percent enantioselectivity.This reaction can be applied to a diene containing a hetero atom such as 2-ethylthio-1,3-butadiene, which affords the Diels-Alder adduct in a high optical purity.In this paper are also described the methods for determining the optical purities of the obtained 4-substituted 3-cyclohexenecarboxylic acid derivatives.
