Dynamic properties of bacteriorhodopsin exposed to ultrashort light pulses

Bacteriorhodopsin (BR) in its metastable form was used for pulsed holographic recording at lambda~400nm . It is shown that the properties of BR are insensitive to changes in the writing light's pulse width. When holograms are recorded in the BR stable form (lambda~600 nm) , the sensitivity of the medium and the diffraction efficiency of those holograms are reduced proportionally to the decrease in the light's pulse width.     

Multiparticle photonuclear reactions in <Superscript>203</Superscript>Tl nuclei

The thallium isotopes ²⁰³Tl and ²⁰⁵Tl were irradiated using a beam of bremsstrahlung gamma quanta with the maximum energy E _γ ^m = 50 MeV from an RTM-70 electron racetrack microtron installed at the Scobeltsyn Nuclear Physics Research Institute (Lomonosov Moscow State University, Russia). The gamma spectra of the residual activity were measured for an irradiated sample. Photonuclear reactions in the ²⁰³Tl nuclei with emission from one to four neutrons were observed experimentally. The relative yields of the reactions ²⁰³Tl(γ,n)²⁰²Tl, ²⁰³Tl(γ,2n)²⁰¹Tl, ²⁰³Tl(γ,3n)²⁰⁰Tl, and ²⁰³Tl(γ,4n)¹⁹⁹Tl were determined for the first time.     

Transformations of (-)-myrtenal epoxide over askanite-bentonite clay

Acid-catalyzed transformations of (-)-myrtenal epoxide over askanite-bentonite clay involve skeletal rearrangements of the pinane framework, leading to an optically active dialdehyde (an analog of campholenic aldehyde), aldehydes having a p-menthane skeleton, and an unusual optically active aldehyde with a bicyclo[3.2.1]octene skeleton.     

Dehydroabietylamine-based thiazolidin-4-ones and 2-thioxoimidazolidin-4-ones as novel tyrosyl-DNA phosphodiesterase 1 inhibitors

Molecular Diversity - Tyrosyl-DNA phosphodiesterase 1 (TDP1) is a DNA repair enzyme that plays a key role in repairing damage caused by various antitumor drugs. It is a promising target in...     

Antiulcerogenic activity of borneol derivatives

Antiulcerogenic activity of borneol and its N-heterocyclic esters was investigated using indomethacin-induced gastric ulcer model. A considerable antiulcerogenic effect comparable to that shown by Omeprazole and Famotidine was found for two investigated compounds in the indomethacin-induced gastric ulcer model. Bornyl 2-piperazinoacetate, with a non-substituted piperazine moiety, showed maximum antiulcerogenic activity in the indomethacininduced gastric ulcer model and demonstrated a significant gastroprotective effect in the ethanol-induced gastric ulcer model comparable to the effect of Omeprazole.

     

New chiral ligands from myrtenal and caryophyllene for asymmetric oxydation of sulfides catalyzed by metal complexes

From myrtenal and caryophyllene, widespread terpene compounds, three new chiral Schiff bases were prepared suitable for ligands in vanadium ions catalyzed sulfides oxidation to chiral sulfoxides.     

The Convenient Way for Obtaining Geranial by Acid‐Catalyzed Kinetic Resolution of Citral

A new simple method has been developed for isolation of geranial from citral, which is a mixture of two isomeric aldehydes, geranial and neral. The storage of citral in the presence of K10 montmorillonite clay has been demonstrated to result in an almost complete conversion of neral to dimeric and oligomeric products, with most geranial remaining unconverted. This enables isolation of geranial with the yield of up to 94%, based on the amount of geranial originally present in citral.     

Discovery of New Ginsenol-Like Compounds with High Antiviral Activity

A number of framework amides with a ginsenol backbone have been synthesized using the Ritter reaction. We named the acetamide as Ginsamide. A method was developed for the synthesis of the corresponding amine and thioacetamide. The new compounds revealed a high activity against H1N1 influenza, which was confirmed using an animal model. Biological experiments were performed to determine the mechanism of action of the new agents, a ginsamide-resistant strain of influenza virus was obtained, and the pathogenicity of the resistant strain and the control strain was studied. It was shown that the emergence of resistance to Ginsamide was accompanied by a reduction in the pathogenicity of the influenza virus.     

Novel Bispidine-Monoterpene Conjugates—Synthesis and Application as Ligands for the Catalytic Ethylation of Chalcones

A number of new chiral bispidines containing monoterpenoid fragments have been obtained. The bispidines were studied as ligands for Ni-catalyzed addition of diethylzinc to chalcones. The conditions for chromatographic analysis by HPLC-UV were developed, in which the peaks of the enantiomers of all synthesized chiral products were separated, which made it possible to determine the enantiomeric excess of the resulting mixture. It was demonstrated that bispidine-monoterpenoid conjugates can be used as the ligands for diethylzinc addition to chalcone C=C double bond but not as inducers of chirality. Besides products of ethylation, formation of products of formal hydrogenation of the chalcone C=C double bond was observed in all cases. Note, that this formation of hydrogenation products in significant amounts in the presence of such catalytic systems was found for the first time. A tentative scheme explaining the formation of all products was proposed.