Enantioselective Synthesis of α-Quaternary Amino Acids by Alkylation of Deprotonated α-Aminonitriles
作者:Isabelle Netz、Murat Kucukdisli、Till Opatz
DOI:10.1021/acs.joc.5b00868
日期:2015.7.2
A series of α-quaternary arylglycines were prepared in high optical purity (up to 98% ee) by α-alkylation of deprotonated α-aminonitriles derived by the Strecker reaction from (4S,5S)-5-amino-2,2-dimethyl-4-phenyl-1,3-dioxane. The procedure includes only chromatographic purification of the final products and is devoid of chromatography or crystallization operations on intermediates to raise the optical
Evaluation of the Edman degradation product of vancomycin bonded to core-shell particles as a new HPLC chiral stationary phase
作者:Garrett Hellinghausen、Diego A. Lopez、Jauh T. Lee、Yadi Wang、Choyce A. Weatherly、Abiud E. Portillo、Alain Berthod、Daniel W. Armstrong
DOI:10.1002/chir.22985
日期:2018.9
macrocyclic glycopeptide‐based chiralstationaryphase (CSP), prepared via Edman degradation of vancomycin, was evaluated as a chiralselector for the first time. Its applicability was compared with other macrocyclic glycopeptide‐based CSPs: TeicoShell and VancoShell. In addition, another modified macrocyclic glycopeptide‐based CSP, NicoShell, was further examined. Initial evaluation was focused on the complementary
Compounds of the present invention include cell growth inhibitors which are peptides of Formula I,
A-B-D-E-F-(G)
r
-(K)
s
-L (I),
and acid salts thereof, wherein A, B, D, E, F, G and K are α-amino acid residues, and s and r are each, independently, 0 or 1. L is a monovalent radical, such as, for example, an amino group, an N-substituted amino group, a β-hydroxylamino group, a hydrazido group, an alkoxy group, a thioalkoxy group, an aminoxy group, or an oximato group. The present invention also includes a method for treating cancer in a mammal, such as a human, comprising administering to the mammal an effective amount of a compound of Formula I in a pharmaceutically acceptable composition.
Compounds of the present invention include cell growth inhibitors which are peptides of Formula I,
A-B-D-E-F-(G)
r
-(K)
s
-L (I),
and acid salts thereof, wherein A, B, D, E, F, G and K are α-amino acid residues, and s and r are each, independently, 0 or 1. L is a monovalent radical, such as, for example, an amino group, an N-substituted amino group, a β-hydroxylamino group, a hydrazido group, an alkoxy group, a thioalkoxy group, an aminoxy group, or an oximato group. The present invention also includes a method for treating cancer in a mammal, such as a human, comprising administering to the mammal an effective amount of a compound of Formula I in a pharmaceutically acceptable composition.
Far superior oxidation catalysts based on macrocyclic compounds
申请人:Carnegie Mellon University
公开号:US10926248B2
公开(公告)日:2021-02-23
An especially robust compound and its derivative metal complexes that are approximately one hundred-fold superior in catalytic performance to the previously invented TAML analogs is provided having the formula:
wherein
Y1, Y2, Y3 and Y4 are oxidation resistant groups which are the same or different and which form 5- or 6-membered rings with a metal, M, when bound to D; at least one Y incorporates a group that is significantly more stable towards nucleophilic attack than the organic amides of TAML activators; D is a metal complexing donor atom, preferably N; each X is a position for addition of a labile Lewis acidic substituent such as (i) H, deuterium, (ii) Li, Na, K, alkali metals, (iii) alkaline earth metals, transition metals, rare earth metals, which may be bound to one or more than one D, (iv) or is unoccupied with the resulting negative charge being balanced by a nonbonded countercation; at least one Y may contain a site that is labile to acid dissociation, providing a mechanism for shortening complex lifetime. The new complexes deliver catalytic performances that promise to revolutionize multiple oxidation technology spaces including water purification.
一种特别强效的化合物及其衍生物金属配合物的催化性能比之前发明的 TAML 类似物高出约 100 倍,其分子式为
其中
Y1、Y2、Y3 和 Y4 是相同或不同的抗氧化基团,在与 D 结合时与金属 M 形成 5 或 6 元环;至少有一个 Y 含有比 TAML 活化剂的有机酰胺对亲核攻击更稳定的基团;D 是金属络合供体原子,最好是 N;每个 X 都是添加易受路易斯酸性取代基的位置,如 (i) H、氘,(ii) Li、Na、K、碱金属,(iii) 碱土金属、过渡金属、稀土金属,这些取代基可与一个或多个 D 结合,(iv) 或未被占用,由此产生的负电荷由非键反离子平衡;至少一个 Y 可包含一个易受酸解离的位点,为缩短络合物寿命提供了机制。新复合物具有催化性能,有望彻底改变包括水净化在内的多个氧化技术领域。