- Total synthesis and cytotoxicity evaluation of an oxazole analogue of tubulysin U
-
Tubulysins are strongly cytotoxic natural tetrapeptides with potent antiproliferative, antimitotic, and antiangiogenic activities which might find use in oncology. We herein report the first total synthesis of a stereoisomerically pure oxazole analogue of
- Shankar, P. Sreejith,Sani, Monica,Saunders, Fiona R.,Wallace, Heather M.,Zanda, Matteo
-
scheme or table
p. 1673 - 1676
(2011/09/15)
-
- Asymmetric syntheses of α-methyl γ-amino acid derivatives
-
This project was undertaken to demonstrate the potential of asymmetric hydrogenations mediated by the chiral, carbene-oxazoline analogue of Crabtree's catalyst "cat" in asymmetric hydrogenations of allylic amine derivatives of amino acids. Peripheral feat
- Zhu, Ye,Khumsubdee, Sakunchai,Schaefer, Amber,Burgess, Kevin
-
scheme or table
p. 7449 - 7457
(2011/11/29)
-
- A versatile annulation protocol toward novel constrained phosphinic peptidomimetics
-
(Chemical Equation Presented) The development of a novel 3-center 2-component annulation reaction between α,ω-carbamoylaldehydes and suitably monoalkylated phosphinic acids is reported. Depending on the starting α,ω-carbamoylaldehyde, diverse phosphinic scaffolds varying in the size of their rigidity element, the nature and stereochemistry of substituents, and the participation of heteroatoms in the azacyclic ring system can be obtained in one synthetic step and in high yield. In addition, this methodology allows the synthesis of Fmoc-protected constrained aminophosphinic acids that can be easily converted to suitable pseudodipeptide building blocks compatible with the requirements of peptide synthesis on the solid phase. Finally, the careful choice of both substituents and protecting groups can provide functionally diverse, orthogonally protected constrained scaffolds for extended derivatization of the target phosphinic peptidomimetic structrures.
- Nasopoulou, Magdalini,Georgiadis, Dimitris,Matziari, Magdalini,Dive, Vincent,Yiotakis, Athanasios
-
p. 7222 - 7228
(2008/02/12)
-
- Facile synthetic route to (2S,3S)-3-amino-2-hydroxy-4-phenylbutyric acid and its derivatives, the key intermediates for HIV protease inhibitors
-
A facile and efficient route to (2S,3S)-3-amino-2-hydroxy-4-phenylbutyric acid and its derivative (4S,5S)-4-benzyl-5-hydroxymethyl oxazolidin-2-one is presented. N-phthaloyl protected L-phenylalanine 1 was treated with thionyl chloride followed by hydroge
- Lei, Lijun,He, Xuchang,Bai, Donglu
-
p. 1535 - 1540
(2007/10/03)
-
- Tetraallylstannane and Weinreb amides: A simple 'green' route to N-protected homoallylic alcohols and allyl ketones
-
We have explored the addition of tetraallylstannane (7) to a variety of N-protected Weinreb amides (N-phthalimido and N-benzyl). Reactions were conducted in methanol and the ionic liquid, butylmethylimidazole tetrafluoroborate (bmim[BF4]), yields of the corresponding N-protected allylketones were moderate to good. Allylation of the corresponding aminoaldehydes gave excellent yields of homoallylic alcohols (68-94%) and moderate to good diastereoselectivities (50-86%). (C) 2000 Published by Elsevier Science Ltd.
- McCluskey,Garner,Young,Caballero
-
p. 8147 - 8151
(2007/10/03)
-
- Synthesis of the HIV-proteinase inhibitor Saquinavir: A challenge for process research
-
The task of process research, namely developing efficient, economically and technically as well as ecologically feasible syntheses in time, is demonstrated on the HIV-proteinase inhibitor Saquinavir (1), a complex molecule comprising six stereo-centres. Based on the first 26-step research synthesis furnishing a 10% overall yield, process research established a new, short 11-step synthesis affording a 50% overall yield.
- Goehring, Wolfgang,Gokhale, Surendra,Hilpert, Hans,Roessler, Felix,Schlageter, Markus,Vogt, Peter
-
p. 532 - 537
(2007/10/03)
-
- Method for the production of aldehydes
-
A process for the manufacture of aldehydes by the catalytic reduction of carboxylic acid halides with hydrogen in the presence of an alkylene oxide.
- -
-
-
- The Influence of Protecting Group Character on the Diastereoselectivity of Thiazolidine Ring Formation from Amino Aldehydes and Cysteine
-
A series of 2-(1'-aminoalkyl)-thiazolidine-4-carboxylic acid derivatives was synthesized by condensation of (R)- or (S)-Cys with the amino aldehydes obtained from N-Boc-protected (S)-Ile, (S)-Leu, O-Bzl-(S)-Tyr, (S)- and (R)-Phe, and N-Z-(S)-Phe, N-Pht-(S)-Phe and N-(Pht)-(R)-Phe. All compounds were studied by 1H NMR and CD. The 2D NOESY experiments were carried out to determine the configuration of the newly formed stereogenic centre in position 2 of the thiazolidine ring. It was found that the configuration on the thiazolidine C2 atom is R or S when N-Boc- and N-Z-(S)-amino aldehydes or N-Boc- and N-Z-(R)-amino aldehydes are used in the reaction, respectively. The situation is opposite in the case of N-Pht-Phe derived amino aldehydes. The relation between the C2 atom configuration and the shape of CD spectra is discussed. Key words: 2-(1'-aminoalkyl)-thiazolidine-4-carboxylic acids, amino aldehydes, cysteine, stereoselectivity, absolute configuration, NMR, CD.
- Wyslouch, Aleksandra,Lisowski, Marek,Siemion, Ignacy Z.
-
p. 117 - 130
(2007/10/02)
-