Results 181 to 190 of about 5,247 (209)

Improvements in Aldol Reactions with Diketopiperazines.

ChemInform, 2004
AbstractFor Abstract see ChemInform Abstract in Full Text.
Juan Francisco González, Elena de la Cuesta, Carmen Avendaño   +2 more
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SYNTHESIS OF DIKETOPIPERAZINES

Canadian Journal of Chemistry, 1963
not available
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PAF inhibitory activity of diketopiperazines: Structure‐activity relationships

Lipids, 1991
AbstractFR900452, a natural product isolated from the culture broth ofStreptomyces phaeofaciens No. 7739, was found to inhibit PAF‐induced rabbit platelet aggregation with an IC50 of 3.7×10−7M. FR900452, 1‐methyl‐3‐[1‐[5‐methylthiomethyl‐6‐oxo‐3‐(2‐oxo‐3‐cyclopenten‐1‐ylidene)‐2‐piperazinyl]ethyl]‐2‐indoline, has an oxocylopentylidene group ...
N, Shimazaki, I, Shima, M, Okamoto, K, Yoshida, K, Hemmi, M, Hashimoto   +5 more
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Diketopiperazines in Peptide and Combinatorial Chemistry

ChemInform, 2003
AbstractFor Abstract see ChemInform Abstract in Full Text.
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Synthesis of Proline-Based Diketopiperazine Scaffolds

The Journal of Organic Chemistry, 2009
A number of natural products with interesting biological properties are based on a diketopiperazine scaffold. In this context, we have developed a diversity oriented and efficient synthetic strategy to highly functionalized proline-based diketopiperazines.
N, Deppermann, A H G P, Prenzel, A, Beitat, W, Maison   +3 more
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Thiolation of symmetrical and unsymmetrical diketopiperazines

Org. Biomol. Chem., 2012
The introduction of sulfur units into a variety of symmetrical and unsymmetrical diketopiperazines (DKPs) is described. We investigated different thiolation methods utilizing several bases and electrophilic sulfur reagents, leading to monomethylthio-, bis(methylthio)-, and epithio-DKPs.
Ruff, B. M., Zhong, S., Nieger, M., Bräse, S.   +3 more
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Comparative Study of the Synthesis and Structural and Physicochemical Properties of Diketopiperazines vs Aza-diketopiperazines

The Journal of Organic Chemistry, 2017
Aza-diketopiperazines (aza-DKPs) represent an underprivileged motif obtained by scaffold hopping of 2,5-diketopiperazines (2,5-DKPs). Herein, we compare the synthesis and the structural and physicochemical properties of aza-DKP 4 vs 2,5-DKP 7. Thus, X-ray and 1H NMR studies show that aza-DKP 4 is a rigid and nonflat scaffold like the 2,5-DKP 7 ...
Regenass, Pierre, Bosc, Damien, Riché, Stéphanie, Gizzi, Patrick, Hibert, Marcel, Karmazin, Lydia, Ganesan, A., Bonnet, Dominique   +7 more
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The Infrared Dichroism of Diketopiperazine

The Journal of Chemical Physics, 1951
The absorption of polarized infrared radiations by diketopiperazine crystal has been measured in the wavelength region from 2.8 to 15μ. From the observed infrared dichroism the assignment of the absorption bands has been made.
Takehiko Shimanouchi, Kenji Kuratani, San-ichiro Mizushima   +2 more
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Microbial degradation of 2,5-diketopiperazines

1998
Enrichment culture of soil samples with cyclo(Gly-Gly) and cyclo(Gly-l-Tyr) as a carbon and/or a nitrogen source resulted in the isolation of Arthrobacter sp. 1-3-1 and the coryneform rod bacterium, strain T-1-3-Y, as the bacteria which most highly assimilated cyclo(Gly-Gly) and cyclo(Gly-l-Tyr), respectively.
Hiroshi Kanzaki, Kazuyoshi Kawazu
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Über 2,5‐Diketopiperazine, II. Die Umsetzung des 2,5‐Diketopiperazins mit Aldehyden und Nitrosoverbindungen

Journal für Praktische Chemie, 1966
AbstractIn der vorliegenden Arbeit wurde die Reaktionsfähigkeit der beiden Methylengruppen im 2,5‐Diketopiperazin durch die Umsetzung mit aromatischen, heterocyclischen und aliphatischen Aldehyden eingehend untersucht. Dabei konnte festgestellt werden, daß auch aliphatische Aldehyde mit in Nachbarschaft zur CO‐Bindung stehenden aktivierenden Gruppen ...
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