The compound, C(15)H(16)N(2)O(2), features a pyrroline ring fused with a seven-membered diazepine ring; the latter system adopts a boat conformation (with the methine C atom as the prow and the two C atoms of the aromatic ring as the stern). A CH(2)-CH(2) segment of the pyrroline ring is disordered over two positions in a 1:1 ratio.
Download full-text PDF |
Source |
|---|---|
| http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2970423 | PMC |
| http://dx.doi.org/10.1107/S1600536809034266 | DOI Listing |
Publication Analysis
Top Keywords
Similar Publications
Enantioselective Aminosilylation of Alkenes by Palladium/Ming-Phos-Catalyzed Tandem Narasaka-Heck/Silylation Reaction.
Adv Sci (Weinh)
September 2024
Engineering Center of Catalysis and Synthesis for Chiral Molecules, Department of Chemistry, Fudan University Shanghai, Shanghai, 200433, China.
A Pd-catalyzed enantioselective aminosilylation of alkenes via tandem Aza-Heck/silylation reaction under Pd/Sadphos catalysis is disclosed. A wide array of oxime esters and silicon reagents are tolerated, furnishing the chiral pyrrolines bearing one quaternary or two contiguous stereocenters in good yield with high enantioselectivity. Not only terminal alkenes but also tri-substituented internal alkenes successfully participate in the reaction, delivering vicinal stereocenters in complete diastereoselectivity and high enantioselectivity.
View Article and Find Full Text PDFHeme d formation in a Shewanella benthica hemoglobin.
J Inorg Biochem
October 2024
T.C. Jenkins Department of Biophysics, Johns Hopkins University, Baltimore, MD 21218, USA. Electronic address:
In our continued investigations of microbial globins, we solved the structure of a truncated hemoglobin from Shewanella benthica, an obligate psychropiezophilic bacterium. The distal side of the heme active site is lined mostly with hydrophobic residues, with the exception of a tyrosine, Tyr34 (CD1) and a histidine, His24 (B13). We found that purified SbHbN, when crystallized in the ferric form with polyethylene glycol as precipitant, turned into a green color over weeks.
View Article and Find Full Text PDFElectronic Structures of an Annulated -Tetraphenylchlorin and a Related Chlorin Analogue Incorporating an 8-Membered Ring through MCD Spectroscopy and DFT Calculations.
J Phys Chem A
June 2024
Department of Chemistry, University of Tennessee, Knoxville, Tennessee 37996, United States.
Herein, we compare the electronic structures of the metal-free and nickel(II) derivatives of an annulated -tetraphenyldihydroxychlorin with those of the (metallo)chlorin analogues derived by pyrroline β,β'-ring cleavage of the annulated (metallo)chlorins. These (metallo)chlorin analogues incorporate 8-membered heterocycles in place of the pyrroline, carry oxo-functionalities on the former pyrroline β-carbon atoms, and were previously shown to possess drastically ruffled (twisted) nonplanar conformations. The magnetic circular dichroism spectra of all chromophores investigated feature chlorin-like UV-vis spectra and correspondingly reversed (positive-to-negative in ascending energy) sign sequences in the -band region, indicative of ΔHOMO < ΔLUMO relationships.
View Article and Find Full Text PDFRapid Access to Divergent Fused Polycycles Via One-Pot A Coupling and Intramolecular Diels-Alder Reaction.
Chemistry
July 2024
Department of Chemistry, The Hong Kong University of Science and Technology, Clear Water Bay, Hong Kong, China.
Divergent nitrogen-containing fused polycyclic ring systems are constructed from simple starting materials via a one-pot aldehyde-alkyne-amine (A) coupling and intramolecular Diels-Alder reaction. This domino reaction directly furnishes linear 5/5/5 and 5/5/6, or nonlinear 5/5/6/5, polycyclic rings containing an oxa-bridged fused 5/5 bicycle and a 1,6-enyne substructure. One-step derivation of the oxa-bridged 5/5 bicycle leads to a polyfunctionalized 5/5 bicycle with tetrahydrofuran fused back-to-back to pyrroline or a 6/5 bicycle with the hexahydro-1H-isoindole structure, while cycloisomerizing the enyne substructure adds an extra fused 5-membered ring to afford functionalized linear 5/5/5/5 or 5/5/5/5/5 fused ring systems from selected substrates.
View Article and Find Full Text PDFHow Do Molecular Tweezers Bind to Proteins? Lessons from X-ray Crystallography.
Molecules
April 2024
Department of Mechanistic Cell Biology, Max-Planck Institute of Molecular Physiology, Otto-Hahn-Straße 11, 44227 Dortmund, Germany.
To understand the biological relevance and mode of action of artificial protein ligands, crystal structures with their protein targets are essential. Here, we describe and investigate all known crystal structures that contain a so-called "molecular tweezer" or one of its derivatives with an attached natural ligand on the respective target protein. The aromatic ring system of these compounds is able to include lysine and arginine side chains, supported by one or two phosphate groups that are attached to the half-moon-shaped molecule.
View Article and Find Full Text PDFWant AI Summaries of new PubMed Abstracts delivered to your In-box?
Enter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!