The diffusion behavior of methanol in different critical media (n-pentane, n-hexane, n-heptane and acetone) was investigated by the Monte Carlo (MC) method. From the simulation results, the diffusion constant of methanol molecule in the critical n-hexane is much larger than those in n-pentane, n-heptane and acetone. By analyzing the microscopic configurations of the critical mixtures, it is fou...

We report the synthesis and properties of alkynyl-functionalised and -bridged bicyclo[1.1.1]pentane derivatives consisting of the heavier group 14 elements silicon and tin.

the reaction kinetics of the isomerization 3,4-dichlorobutene-1 to 1,4-dichlorobutene-2 was investigated by using gas-liquid chromatography method in the presence of fe2o3/mgo as solid catalyst in the temperature range 25-55°c. fe2o3/mgo has been prepared by the support saturation method, tested in the isomerization of 3, 4-dichlorobutene-1 into 1, 4-dichlorobutene-2. this catalyst shows a high...

Extraction with pentane virtually abolished reduced nicotinamide adenine dinucleotide oxidase activity in small particles from Azotobacter vinelandii, but activity was largely restored by added ubiquinone.

In the title mol-ecule, C(30)H(52)O(4), the three six-membered rings are in chair conformations, the cyclo-pentane ring is in an envelope form and the tetra-hydro-furan ring has a conformation inter-mediate between half-chair and sofa. In the crystal, mol-ecules are linked by inter-molecular O-H⋯O hydrogen bonds into helical chains along [100]. Two intra-molecular O-H⋯O hydrogen bonds are also ...

In the title compound, C(18)H(21)IO, the cyclo-hexane ring adopts a chair conformation, whereas the cyclo-pentane ring and the ten-membered tetra-line portions each adopt an envelope conformation. For the five-membered ring, the methine C atom deviates by 0.638 (4) Å (r.m.s. of the four other atoms is 0.005 Å) and for the ten-membered ring, the methine C atom constituting the flap deviates by 0...

Biological signal transduction by photoactive yellow protein (PYP) in halophilic purple sulfur bacteria is initiated by trans-to-cis isomerization of the p-coumaric acid chromophore (pCa) of PYP. pCa is engaged in two short hydrogen bonds with protein residues E46 and Y42, and it is negatively charged at the phenolate oxygen. We investigated the role in the isomerization process of the E46 shor...

We report a two-step approach to obtain synthetically versatile bicyclo[1.1.1]pentane (BCP) derivatives using Grignard reagents. This method allows the incorporation of BCP units in tetrapyrrolic macrocycles and synthesis new class calix[4]pyrrole analogues by replacing two bridging methylene groups with units. In addition, doubly N-confused system was also formed presence electron-withdrawing ...