62222-08-6Relevant academic research and scientific papers
Tautomerism and atropisomerism in free-base (meso)-strapped porphyrins: Static and dynamic aspects
Urbani, Maxence,Torres, Tomas
, p. 16337 - 16349 (2014)
We report herein some outstanding examples of atropisomerism and tautomerism in five (meso-)strapped porphyrins. Porphyrins S0-S4 have been synthesised, characterised and studied in detail by spectroscopic and spectrometric techniques, and their isomeric purity verified by HPLC analysis. In particular, they exhibit perfectly well-defined NMR spectra that display distinct patterns depending on their average symmetry at room temperature: C2v D2d, C2h, C2v and D2h for S0-S4, respectively. NH tautomerism was evidenced by variable-low-temperature 1H NMR experiments in [D2]dichloromethane performed on S0 (δG?298K = 48± 1 kJmol-1) and S1 (δG?298K = 55±3 kJmol-1), which has led to an understanding of the average spectra observed for the five porphyrins at room temperature. On the other hand, S2 and S3 are stable atropisomers at room temperature, easily separated and characterised, as a result of restricted rotation of their strapped bridges due to their high rotational barrier energies. Upon heating to 82 °C, they slowly equilibrate to a thermodynamic ratio of 64:36 in favour of the more stable S2 isomer. This atropisomerisation process was evidenced by 1H NMR spectroscopy and monitored by HPLC, from which high rotational energy barriers of 115.2 (δG?S3) and 116.9 kJ mol-1 (δG?S3) were deduced.
MONOMER AND MULTIMERIC ANTI-HBV AGENTS
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Page/Page column 143; 163; 164, (2020/05/15)
The present invention is directed to compounds, compositions and methods for preventing, treating or curing hepatitis B (HBV) infection in human subjects or other animal hosts. The compounds are as also pharmaceutically acceptable, salts, prodrugs, and other derivatives thereof as pharmaceutical compositions and methods for treatment, prevention or eradication of HBV infection.
Both-faces Hindered Porphyrins. Part 1. Synthesis and Characterization of Basket-handle Porphyrins and Their Iron Complexes
Momenteau, Michel,Mispelter, Joel,Loock, Bernard,Bisagni, Emile
, p. 189 - 196 (2007/10/02)
The synthesis of the 'both-faces' hindered porphyrins using two different methods is reported.These so-called 'basket-handle' porphyrins (BHP) are derived from 5,10,15,20-tetraphenylporphyrin in which two opposite phenyl groups are bridged by alkylene or arylene-p-bisalkylene chains.In addition to the desired compounds , two other isomers were obtained .These were separated by t.l.c. on silica gel and then individually characterized.The structural assignment of the three isomers in the five series studied was based on the 1H n.m.r. spectra of the free bases and of their iron(II) complexes.
SYNTHESES AND OXYGENATION OF IRON(II) "STRAPPED" PORPHYRIN COMPLEXES
Baldwin, Jack E.,Crossley, Maxwell J.,Klose, Thomas,O'Rear, Edgar A.,Peters, Mary K.
, p. 27 - 40 (2007/10/02)
A general route to 'strapped' porphyrins which are bridged between diagonally opposite meso-positions is described.Studies on the oxygenation and carbonylation of their iron(II) complexes have shown that they are inferior to 'capped' porphyrins as models
