24336-20-7Relevant articles and documents
Synthesis of C11-to-C14 methyl-shifted all-: Trans -retinal analogues and their activities on human aldo-keto reductases
Alvarez, Rosana,Barracco, Vito,De Lera, Angel R.,Domínguez, Marta,Farrés, Jaume,Jiménez, Rafael,López, Susana,Parés, Xavier,Pequerul, Raquel,Rivas, Aurea
, p. 4788 - 4801 (2020/07/13)
Human aldo-keto reductases (AKRs) are enzymes involved in the reduction, among other substrates, of all-trans-retinal to all-trans-retinol (vitamin A), thus contributing to the control of the levels of retinoids in organisms. Structure-activity relationship studies of a series of C11-to-C14 methyl-shifted (relative to natural C13-methyl) all-trans-retinal analogues as putative substrates of AKRs have been reported. The synthesis of these retinoids was based on the formation of a C10-C11 single bond of the pentaene skeleton starting from a trienyl iodide and the corresponding dienylstannanes and dienylsilanes, using the Stille-Kosugi-Migita and Hiyama-Denmark cross-coupling reactions, respectively. Since these reagents differ by the location and presence of methyl groups at the dienylorganometallic fragment, the study also provided insights into the ability of the different positional isomers to undergo cross-coupling and the sensitivity of these processes to steric hindrance. The resulting C11-to-C14 methyl-shifted all-trans-retinal analogues were found to be active substrates when tested with AKR1B1 and AKR1B10 enzymes, although relevant differences in substrate specificities were noted. For AKR1B1, all analogues exhibited higher catalytic efficiency (kcat/Km) than parent all-trans-retinal. In addition, only all-trans-11-methylretinal, the most hydrophobic derivative, showed a higher value of kcat/Km = 106 000 ± 23 200 mM-1 min-1 for AKR1B10, which is in fact the highest value from all known retinoid substrates of this enzyme. The novel structures, identified as efficient AKR substrates, may serve in the design of selective inhibitors with potential pharmacological interest. This journal is
Synthetic control of retinal photochemistry and photophysics in solution
Bassolino, Giovanni,Sovdat, Tina,Liebel, Matz,Schnedermann, Christoph,Odell, Barbara,Claridge, Timothy D.W.,Kukura, Philipp,Fletcher, Stephen P.
, p. 2650 - 2658 (2014/03/21)
Understanding how molecular structure and environment control energy flow in molecules is a requirement for the efficient design of tailor-made photochemistry. Here, we investigate the tunability of the photochemical and photophysical properties of the retinal-protonated Schiff base chromophore in solution. Replacing the n-butylamine Schiff base normally chosen to mimic the saturated linkage found in nature by aromatic amines results in the reproduction of the opsin shift and complete suppression of all isomerization channels. Modification of retinal by directed addition or removal of backbone substituents tunes the overall photoisomerization yield from 0 to 0.55 and the excited state lifetime from 0.4 to 7 ps and activates previously inaccessible reaction channels to form 7-cis and 13-cis products. We observed a clear correlation between the presence of polarizable backbone substituents and photochemical reactivity. Structural changes that increase reaction speed were found to decrease quantum yields, and vice versa, so that excited state lifetime and efficiency are inversely correlated in contrast to the trends observed when comparing retinal photochemistry in protein and solution environments. Our results suggest a simple model where backbone modifications and Schiff base substituents control barrier heights on the excited-state potential energy surface and therefore determine speed, product distribution, and overall yield of the photochemical process.
Synthesis of specifically deuteriated 9- and 13-demethylretinals
Berg, Ellen M. M. van den,Bent, Arie van der,Lugtenburg, Johan
, p. 160 - 167 (2007/10/02)
(13-2H)13-Demethylretinal, (11,12,13-2H3)13-demethylretinal, (9-2H)9-demethylretinal and (9,10-2H2)9-demethylretinal were prepared in all-E, 9Z, 11Z and 13Z isomeric form with high deuterium incorporation.In the
