- Allosteric modulation of the dopamine receptor by conformationally constrained type VI β-turn peptidomimetics of Pro-Leu-Gly-NH2
-
A peptidomimetic of Pro-Leu-Pro-NH2, 7, possessing an indolizidinone type VI β-turn mimic was synthesized via improved high-yielding protocols for the preparation and Cbz protection of α-allylproline. Bicyclic peptidomimetic 7 and spirobicylic
- Vartak, Ashish P.,Skoblenick, Kevin,Thomas, Nancy,Mishra, Ram K.,Johnson, Rodney L.
-
p. 6725 - 6729
(2008/09/17)
-
- Enantioselective total synthesis of avrainvillamide and the stephacidins
-
In this article, full details regarding our total synthesis of avrainvillamide and the stephacidins are presented. After an introduction and summary of prior synthetic studies in this family of structurally complex anticancer natural products, the evoluti
- Baran, Phil S.,Hafensteiner, Benjamin D.,Ambhaikar, Narendra B.,Guerrero, Carlos A.,Gallagher, John D.
-
p. 8678 - 8693
(2007/10/03)
-
- Short, enantioselective total synthesis of stephacidin A
-
A concise route to the heptacyclic indole alkaloid stephacidin A (1) includes a simple method for the gram-scale synthesis of substituted tryptophans, a remarkable indole annulation, and the first enolate coupling of an amide to an ester. This synthesis s
- Baran, Phil S.,Guerrero, Carlos A.,Ambhaikar, Narendra B.,Hafensteiner, Benjamin D.
-
p. 606 - 609
(2007/10/03)
-
- Intramolecular catalysis of amide isomerization: Kinetic consequences of the 5-NH- -N(a) hydrogen bond in prolyl peptides
-
The presence of an intramolecular hydrogen bond has been proposed to play a key role in the catalysis of amide isomerization by peptidylprolyl isomerases (PPIases), which are highly conserved and ubiquitous rotamase enzymes that catalyze the cis-trans iso
- Cox, Christopher,Lectka, Thomas
-
p. 10660 - 10668
(2007/10/03)
-
- Novel bicyclic lactams as XaaPro type VI β turn mimics: Design, synthesis, and evaluation
-
The design, enantioselective synthesis, and structural characterization of novel bicyclic lactams as peptide mimics of the type VI β turn is described. The mimics duplicate the conformation of the backbone and disposition of the side-chain atoms of the central two residues of the turn. The Gly L-Pro mimic, lactam 6, was prepared in good overall yield starting from (S)-2-(2'-propenyl)proline. 1H NMR spectroscopy defined the relative stereochemistry of the substituents and conformational characteristics of the six-membered ring of the lactam; X-ray crystallographic analysis confirmed the conformational and stereochemical assignment. Examination of the crystal structure of lactam 6 revealed that the central amide bond was twisted appreciably out of planarity. The twisting of the amide bond was attributed to angle strain resulting from the presence of the sp2-hybridized nitrogen atom at the junction of the two rings. Alkylation of the enolate of the N,N-dimethylformamidine derivative of lactam 6 with benzyl bromide afforded stereoselectively the formamidine 11, a mimic of an L-Phe L-Pro dipeptide in the type VI turn conformation. The efficient synthetic route to highly functionalized peptidomimetics such as 11 will prove highly useful in peptide structure-function studies.
- Kim, Kyonghee,Dumas, Jean-Philippe,Germanas, Juris P.
-
p. 3138 - 3144
(2007/10/03)
-
- DESIGN, SYNTHESIS AND EVALUATION OF A NOVEL BICYCLIC LACTAM AS A GLY-PRO TYPE VI BETA-TURN MIMIC
-
The stereoselective synthesis and conformational evaluation of Gly-Pro type VI turn mimic 7, the first mimetic to constrain the central three bonds and incorporate the side chain groups of a beta-turn, is described.A superimposition of the crystallographi
- Dumas, Jean-Philippe,Germanas, Juris Paul
-
p. 1493 - 1496
(2007/10/02)
-