80745-07-9Relevant articles and documents
Advantage of in situ generation of N-arylsulfonyl imines from α-amide sulfones in the phase-transfer-catalyzed asymmetric Strecker reaction
Ooi, Takashi,Uematsu, Yukitaka,Fujimoto, Jun,Fukumoto, Kazuhiro,Maruoka, Keiji
, p. 1337 - 1340 (2007/10/03)
Highly efficient, catalytic enantioselective synthesis of N-arylsulfonyl α-amino nitriles from the corresponding α-amido sulfones has been achieved under toluene-aqueous potassium cyanide biphasic conditions using chiral quaternary ammonium iodide (R,R,R)-1 as an effective phase-transfer catalyst. This Strecker synthesis involving the in situ generation of the reactive N-sulfonyl imines is advantageous for the cyanation of the substrates having primary and secondary alkyl substituents.
Method for protecting guanidino group and restoring the same
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, (2008/06/13)
A guanidino group in an amino acid or a peptide can be protected with a specific group, i.e. pentamethylbenzensulfonyl, 2,4,6-trimethoxybenzenesulfonyl, 4-methoxy-2,3,5,6-tetramethylbenzenesulfonyl, 4-methoxy-2,6-dimethylbenzenesulfonyl or 4-methoxy-2,3,6-trimethylbenzenesulfonyl, and said group may easily be removed without affecting the amino acid or the peptide to be derived from the protected amino acid or peptide. Thus, the present invention is useful in the synthesis of peptides containing the guanidino group.