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Search for "cis–trans isomerism" in Full Text gives 7 result(s) in Beilstein Journal of Organic Chemistry.
First series of N-alkylamino peptoid homooligomers: solution phase synthesis and conformational investigation
Beilstein J. Org. Chem. 2022, 18, 845–854, doi:10.3762/bjoc.18.85
- antiparallel arrangement of mirror image molecules held together via two hydrogen bonds in the crystal lattice of dimer 2. Keywords: cis/trans isomerism; peptoid; structure; trans-inducing side chain; Introduction The term “peptoids” refers to the family of artificial oligo(poly)mers consisting of N
Photosensitized direct C–H fluorination and trifluoromethylation in organic synthesis
Beilstein J. Org. Chem. 2020, 16, 2151–2192, doi:10.3762/bjoc.16.183
Polarity effects in 4-fluoro- and 4-(trifluoromethyl)prolines
Beilstein J. Org. Chem. 2020, 16, 1837–1852, doi:10.3762/bjoc.16.151
- C4-exo conformation of the pyrrolidine ring. Keywords: amino acids; cis–trans isomerism; fluorine; polarity; proline; Introduction Polarity is among the key features essential for understanding the behavior of organic molecules of biological origin. In particular, there is a set of polarity-related
cis–trans-Amide isomerism of the 3,4-dehydroproline residue, the ‘unpuckered’ proline
Beilstein J. Org. Chem. 2016, 12, 589–593, doi:10.3762/bjoc.12.57
- the cis–trans isomerism of the peptidyl-Pro amide bond. Elucidation of the roles of Pro in chemical or biological systems and engineering of its features can be addressed with various Pro analogues. Here we report an experimental work investigating the basic physicochemical properties of two Pro
- /cis ratios compared to that of Pro and 4-trifluoromethylproline derivatives. Finally we demonstrate that the 3,4-double bond in the investigated structures leads to an increase of the amide rotational barriers, presumably due to an interplay with the transition state. Keywords: amino acids; cis–trans
- isomerism; fluorine; pKa; proline; Introduction The sole genetically encoded secondary amino acid proline (Pro, 1) is known for its unique properties in biological systems. In particular, Pro residues are often found in the s-cis peptidyl-Pro conformation, due to the low energy difference between the s
Advances in the synthesis of functionalised pyrrolotetrathiafulvalenes
Beilstein J. Org. Chem. 2015, 11, 1112–1122, doi:10.3762/bjoc.11.125
- and Becher to develop pyrrole-annelated TTF derivatives: monopyrrolotetrathiafulvalenes (MPTTFs, 4) and bispyrrolotetrathiafulvalenes (BPTTFs, 5) (Figure 2) [4][25]. The presence of either one or two fused pyrrole rings, respectively, eliminates cis–trans isomerism whilst still allowing for further
Total synthesis and cytotoxicity of the marine natural product malevamide D and a photoreactive analog
Beilstein J. Org. Chem. 2014, 10, 316–322, doi:10.3762/bjoc.10.29
- ). In the NMR spectra, four sets of signals were observed because of additional cis/trans isomerism of the acyl pyrrolidine moiety. As in the case of 1, the tripeptidic western half showed mostly broad signals, whereas the signals of the phenyl carbons are resolved better, even if not fully separated
Exceptionally small supramolecular hydrogelators based on aromatic–aromatic interactions
Beilstein J. Org. Chem. 2011, 7, 167–172, doi:10.3762/bjoc.7.23
- -isomer during UV irradiation. Thus, we infer that the formation of two layers in the gel IV after UV irradiation originates from geometric (cis/trans-) isomerism. Compound 6 also exhibits another interesting phenomenon. On acidification by 1N HCl solution, the solution of 6 (Figure 2A, 2.0 wt %) first
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