(2S,4R)- and (2S,4S)-perfluoro-tert-butyl 4-hydroxyproline were synthesized (as Fmoc-, Boc-, and free amino acids) in 2-5 steps. The key step of each synthesis was a Mitsunobu reaction with perfluoro-tert-butanol, which incorporated a perfluoro-tert-butyl group, with nine chemically equivalent fluorines. Both amino acids were incorporated in model α-helical and polyproline helix peptides. Each ...

Three volatile components, namely benzoic acid ethyl ester (1), 2,6-di-tert-butyl-p-benzoquinone (BHT-quinone) (2), and 3,5-di-tert-butyl-4-hydroxybenzaldehyde (BHT-CHO) (3), were detected from the gas in the capsules of Asclepias physocarpa by means of GC/MS analysis. BHT-quinone and BHT-CHO as organic pollutants are the degradation products of the antioxidant 2,6-di-tert-butyl-4-methylphenol ...

plastic adhesives, normal butyl cyanoacrylate monomer, isobutyl cyanoacrylate monomer and methyl 2 _ cyaooacrylate monomer, have been utilized in a comparative study with 5-{) silk suture in the repair of transected carotid arteries. follow _ up arteriog rams indicate isobutyl cyanoacrylate monomer and normal butyl cyanoacrylate monomer as having the most impressive rerults with only two thromb...

1-butyl-3-methylimidazolium bromide ([bmim]br) as an ionic liquid promoted selectively oxidation of aliphatic and aromatic sulfides to the corresponding sulfoxides and the oxidative coupling of thiols to disulfides by nabro3 in excellent yields under neutral conditions.

deprotection of phosphate, phosphate, and sulfite esters by silica chloride is described. silica chloride is a mild, selective, and effective reagent for cleavage of benzyl and t-butyl esters of the above compounds.

Synthesis of 4-[(2/4-chloro-/2,3-dichloro-/2/4-bromo-/2,4-dinitro-/4-nitrophenyl) anilinemethyl]6-t-butyl-2H-1-benzopyran-2-ones have been carried out. Synthesized compounds were characterized by 1HNMR, IR and other physical and analytical data. All of the synthesized compounds were evaluated for their antifungal activity against Aspergillus awamori and Sclerotium rolfsii and antibacterial acti...

The influence of water-miscible alcohols (methanol, 1-propanol, 2-propanol, and t-butyl alcohol) on the isomerization of glucose to fructose and mannose was investigated under subcritical aqueous conditions (180-200 °C). Primary and secondary alcohols promoted the conversion and isomerization of glucose to afford fructose and mannose with high and low selectivity, respectively. On the other han...

Addition of an excess of t-butyl isocyanide to solid Mo2 (0, CCF3 )4 or MO?_ (0, CMe)4 gives (t-BuNC), Mo(Oz CCF3 )* or (t-BuNC), Mo(Oz CMe), , respectively. The quadruple bond in K4 MO* Cl8 or Cl4 MO, (n-Bus P)4 also can be cleaved by an excess of t-butyl isocyanide to yield (t-BuNC), MoCl, _ The anionic ligands can be exchanged with ammonium hexafluorophosphate in presence of excess t-BuNC to...

We report the ambient-temperature synthesis of novel (E)-N-(3-(tert-butyl)-1-methyl-1H-pyrazol-5-yl)-1-(pyridin-2-yl)methanamine 3 in 81% yield by a condensation reaction between 3-(tert-butyl)-1-methyl-1H-pyrazol-5-amine 1 and 2-pyridinecarboxaldehyde 2 methanol using magnesium sulfate as drying agent. The N-pyrazolyl imine was full characterized IR, 1D, 2D NMR spectroscopy, mass spectrometry,...

Abstract To separate the azeotropic mixture n-butyl acetate and n-butanol by liquid–liquid extraction, three ionic liquids (ILs) 1-ethyl-3-methylimidazolium dihydrogen phosphate ([Emim]H2PO4), 1-butyl-3-methylimidazolium ([Bmim]H2PO4) 1-hexyl-3-methylimidazolium ([Hmim]H2PO4) were adopted as extractants. The equilibrium data for ternary mixtures (n-butyl acetate + n-butanol + [Emim]H2PO4/[Bmim]...