To examine the effects of coordination sites and nature ligands reported for color-tuning a few cyclometalated Ir(III) complexes, series 3'-substituted (F, CH3, OCH3, CF3) phenylisoquinoline (piq) were synthesized successfully used to prepare iridium including bis[1-(5'-methyl)phenylisoquinolinato-N,C2']iridium(III) (acetylacetonate) (6a1), bis[1-(5'-trifluoromethyl)phenylisoquinolinato-N,C2']iridium(III) (6a2), bis[1-(5'-methoxy)phenylisoquinolinato-N,C2']iridium(III) (6a3),...

This study investigated whether and how pirenoxine (PRX) interacts with selenite or calcium ions, as these two ions have been proven respectively a factor leading to the formation of lens cataract. UV, NMR, isothermal titration calorimetry (ITC) analysis indicated that PRX could bind maximum up six anions binding site preference was concentration dependent peripheral first followed by π-π interactions aromatic moiety; while for cation interaction 3-carboxylate β-ketoimine functional groups...

Recent studies have focused on the nanoformulations of curcumin to enhance its solubility and bioavailability. The medicinal properties curcumin-C3 complex, which is a combination three curcuminoids (curcumin, demethoxycurcumin bisdemethoxycurcumin) less explored.The aim this study was prepare encapsulated in chitosan nanoparticles, characterize evaluate their antioxidant antibacterial potential.Ionic gelation method used nanoparticles characterized by Fourier transform infrared...

Abstract Assuming various ionic states in liquids (ILs) are equilibrium with exchange rates too high to be distinguished by NMR experiments and the overall response of measured diffusivity is viewed as sum weighted responses all possible components, ratio cation anion diffusivity, D + / − , a specified IL affords physical meaning: relative association degrees observed anion‐containing components cation‐containing components. These values decrease increasing temperature showing between...

The curcumin-C3 (cur-C3) complex obtained from Curcuma longa rhizome is a combination of three curcuminoids, namely, curcumin, dimethoxycurcumin, and bisdemethoxycurcumin. Cur curcuminoids have been extensively researched for their wide range therapeutic properties against inflammatory diseases, diabetes, cancer.In spite extensive medicinal properties, cur poor solubility bioavailability due to hydrophobicity. This limitation can be overcome by complexing cur-C3 with natural cyclic...

The aim of this study was to investigate the effect storage temperature on color loss (betacyanin degradation) Djulis (Chenopodium formosanum Koidz.) extracts in various alcohol (10-60% EtOH) model systems. All samples were thermally processed and stored at 20-50 °C for 21 days after pigment regeneration. Results showed that betacyanin degradation index (DI) accelerated by ethanol temperature. rate during followed first-order reaction kinetics. higher concentration corresponded loss, which...

Abstract Carbonyls' 2π orbital populations, [2π], in W(CO) 5 L {L = PPh 3 , 2 Me, PPhMe } have been determined by NMR spin‐lattice relaxation techniques. Experimental values of axial compared with those reported for PMe and P(OMe) reveal that is a slightly better π‐acid than . Through space interactions between carbonyl phenyl groups are insignificant since [2π] do not vary significantly the series phosphines, going from PMep to Natural bond (NBO) studies indicate π‐accepting capabilities...

Abstract D julis is a T aiwanese cereal plant containing betacyanin pigment. The aim of this study was to elucidate the relative effect ethanol (10–80%) and p H (3.5 5.5) on pigment stability in aqueous extracts julis. Organic acids were further used investigate their effects color protection. All samples thermally processed (60 C , 30 min) stored (25 21 days) after regeneration (4 24 h). Results showed that promoted degradation extract. hypsochromic shift (decrease λ max ) isomerization...

Abstract Both C‐H bonding and antibonding (σ CH σ* ) of a methyl group would contribute to the highest occupied or lowest unoccupied molecular orbitals (HOMO LUMO) in methylated derivatives Ir(ppz) 2 3 iq (ppz = 1‐phenylpyrazole 3iq isoquinoline‐3‐carboxylate). This is found by analysis HOMO (or formed linear combination bond using natural orbital (NBO) method. The elevated level uniformly for each derivative, indicating σ ‐destabilization outweighs ‐stabilization. To broaden HOMO‐LUMO gap,...

Abstract Analysis of carbonyl's 2π orbital populations, [2π], obtained by NMR relaxation time experiments VIB M(CO)(ẽ 6 ‐C H ) reveals the 3d < 4d 5d trend for M r̊ CO back‐donation, as reported values [2π] M(CO) 5 (quinuclidine). The same analysis performed on Mn(CO) 3 (ẽ C and Re(CO) also gives order back‐donation. distinctive ∼ > has been investigated second‐order perturbation theory within natural bond (NBO) scheme to search orbital‐based explanations. Besides conventional d π...

Abstract A review of sydnone chemistry is divided into two major parts, describing methods developed to prepare derivatives and syntheses starting from sydnones. Spectral studies the structural characterization sydnones are summarized in conclusion.

Abstract The character of the molecular orbitals can be better accounted for in terms adapted atomic and Fock matrix expanded these orbital sets. A clean‐cut unique criterion diradicals covalent bonds given both restricted unrestricted Hartree‐Fock wavefunctions. Instead picture that overlap charge migrates into bonding region, new analysis displays another densities electrons with α β spins give rise to two opposite spin density shifts. If one shifts from atom toward B then it is vice versa...

Abstract The pi‐nature of a CF 3 group can be understood through analysis its bond orbitals (BOs) mixed into the pi‐type molecular ‐substituted Ir(ppy) 2 MDPA + complexes (ppy=2‐phenyl‐pyridine and MDPA=methylated 2,2′‐dipyridyl amine). It has been found that, this natural orbital analysis, parent’s (MOs) stabilized by χρ * BO via negative hyperconjugation and, simultaneously, destabilized electron lp(F) BO. Since these two competing pi‐effects are virtually counterbalanced as indicated...

Abstract Weinhold's natural hybrid orbitals can be chosen as the molecular adapted atomic to build canonical of N 2 molecules. The Fock matrix expanded in reveal deeper insight electronic structure and reaction molecule. For example, magnitude F ab signify bonding character paired electrons well diradical unpaired for both σ‐ π‐types. Discarding concept overlap between non‐orthogonal orbitals, different spins unrestricted Hartree‐Fock wavefunction that there are three pairs opposite spin...

Abstract The symmetrical 2,2′‐disubstitued derivatives of diphenyl disulfide showing widely spanning rates electrophilic attack the HIV‐1 nucleocapsid protein p7 zinc fingers have been rationalized, based on lowest unoccupied molecular orbital (LUMO)‐lowering approach, by substituents' π‐effects and hydrogen bond stabilization effects. In 2,2′‐amide‐ 4,4′‐N‐amide‐substituted derivatives, extent LUMO lowering has reduced destabilization lone‐pair orbital, lp(N), present nitrogen atom N‐amide....

Abstract The higher anti‐human immunodeficiency virus activity of a symmetrical 2,2′‐disubstitued derivative diphenyl disulfide (DPDS) has been explained by the lower energy lowest unoccupied molecular orbital (LUMO), resulted from better hydrogen bond stabilization σ* SS (BO). This conclusion entails participation BO in constructing LUMO. content BO, compared to π* CC BOs phenyl groups, LUMO DPDS found through analysis expanded space. high (%σ* ) laid foundation for formation σ‐type radical...

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