Efficient Synthesis of 3-Aminocyclobut-2-en-1-ones: Squaramide Surrogates as Potent VLA-4 Antagonists
摘要:
[GRAPHICS]A novel series of uniquely functionalized 3-aminocyclobut-2-en-1-ones has been prepared by facile condensation of a variety of cyclobuta-1,3-diones with a phenylalanine-derived primary amine. These systems subsequently lend themselves to substitution at C-2 by reaction with a variety of electrophilic reagents including N-halosuccinimides, sulfenyl chlorides, and Eschenmoser's salt. Compounds from this novel series are potent antagonists of VLA-4.
Efficient Synthesis of 3-Aminocyclobut-2-en-1-ones: Squaramide Surrogates as Potent VLA-4 Antagonists
摘要:
[GRAPHICS]A novel series of uniquely functionalized 3-aminocyclobut-2-en-1-ones has been prepared by facile condensation of a variety of cyclobuta-1,3-diones with a phenylalanine-derived primary amine. These systems subsequently lend themselves to substitution at C-2 by reaction with a variety of electrophilic reagents including N-halosuccinimides, sulfenyl chlorides, and Eschenmoser's salt. Compounds from this novel series are potent antagonists of VLA-4.
Utilizing the high dielectric constant of water: efficient synthesis of amino acid-derivatized cyclobutenones
作者:Jun Li、Yongbin Han、Teresa B. Freedman、Shifa Zhu、Deborah J. Kerwood、Yan-Yeung Luk
DOI:10.1016/j.tetlet.2008.01.121
日期:2008.3
This work reports the use of water as a solvent to facilitate an efficient syntheses of amino acid-derivatized cyclobutenone. Kinetics studies in different solvents reveals that high dielectric constants of the solvents are the primary attribute for the highyielding and fast rate for this reaction. This class of substitution reactions in water also proceeds efficiently with a wide range of amino acids