Fischer,E.; Roesner, Justus Liebigs Annalen der Chemie, 1910, vol. 375, p. 202
作者:Fischer,E.、Roesner
DOI:——
日期:——
Bergmann; Ensslin, Justus Liebigs Annalen der Chemie, 1926, vol. 448, p. 41
作者:Bergmann、Ensslin
DOI:——
日期:——
The Ugly Duckling Metamorphosis: The Ammonia/Formaldehyde Couple Made Possible in Ugi Reactions.
作者:Thaissa Pasquali F. Rosalba、Samia Sayegh A. Kas、Ana Beatriz S. Sampaio、Carlos Eduardo M. Salvador、Carlos Kleber Z. Andrade
DOI:10.1002/ejoc.202001671
日期:2021.5.26
The ammonia/formaldehyde couple (the ugly duckling in Ugi reactions) was finally made possible using hexamethylenetetramine (HMTA) as an efficient formaldehyde surrogate. Various NH-free Ugi adducts were obtained in moderate to excellent yields and two of them were converted to diketopiperazines (DKPs).
Amide bond hydrolysis in peptides and cyclic peptides catalyzed by a dimeric Zr(iv)-substituted Keggin type polyoxometalate
作者:Hong Giang T. Ly、Gregory Absillis、Tatjana N. Parac-Vogt
DOI:10.1039/c3dt50705j
日期:——
reactions exhibited a bell-shaped profile with the fastest hydrolysis observed in the pD range of 5.5–6.0. Interaction of 1 with Gly-Ser and Gly-Gly via their amine nitrogen and amide oxygen was proven by 13C NMR spectroscopy. The effective hydrolysis of Gly-Ser in the presence of 1 is most likely a combination of the polarization of the amide oxygen due to its binding to the Zr(IV) ion in 1 and the
关于水解的详细动力学研究 甘氨酰丝氨酸 (甘氨酸) 和 甘氨酰甘氨酸 (甘氨酸)在二聚锆的存在(IV) -取代的Keggin型多金属氧酸盐(ET 2 NH 2)8 [α-PW 11 ø 39的Zr(μ-OH)(H 2 O)} 2 ]·7H 2 O(1)通过1 H,13 C和31 P NMR光谱学的组合进行。观察到的水解速率常数甘氨酸 和 甘氨酸在pD 5.4和60°C时,分别为63.3×10 -7 s -1和4.44×10 -7 s -1,与未催化反应相比,具有显着的加速作用。两种反应速率常数的pD依赖性显示出钟形曲线,在5.5-6.0的pD范围内观察到最快的水解作用。相互作用1与甘氨酸 和 甘氨酸 13 C NMR光谱证实了它们通过胺氮和酰胺氧的作用。有效水解甘氨酸在1的存在下,最有可能是由于酰胺氧的极化与1中的Zr(IV)离子的结合以及酰胺羰基碳上的Ser羟基的分子内侵蚀所致。还研究