Synthesis and molecular structure of di(4-hydroxy-2,6-diisoborn-2-ylphenyl)methane

Di(4-hydroxy-2-{(1R*,2S*,4S*)-1,7,7-trimethylbicyclo[2.2.1]hept-2-yl}-6-{(1S*,2R*,4R*)-1,7,7-trimethylbicyclo[2.2.1]hept-2-yl})methane was synthesized by condensation of the meso-diastereomer of 2,6-diisobornylphenol with paraformaldehyde under acid catalysis. The product structure as a meso-forms was confirmed by XRD analysis.     

Prenylation of 4-Methylphenol

Russian Journal of General Chemistry - Organoaluminum (aluminum phenolate and aluminum isopropylate) and acidic heterogeneous catalysts (zeolites C-10, C-100 and ZSM, clay KSF, sulfonic cation...     

Alkylation of 2,4-dimethylphenol with (+)-α- and (−)-β-pinenes in the presence of aluminum xylenolate

Alkylation of 2,4-dimethylphenol with (+)-α- and (?)-β-pinenes in the presence of aluminum 2,4-dimethylphenoxide generated in situ led to the formation of mixtures of products, from which optically active compounds were isolated. The structure of 2-bornyl-4,6-dimethylphenol was determined by X-ray analysis; its (+)- and (?)-enantiomers were assigned (1R,2R,4S) and (1S,2S,4R) configurations, respectively.     

Isobornylchalcones as Scaffold for the Synthesis of Diarylpyrazolines with Antioxidant Activity

The pyrazoline ring is defined as a “privileged structure” in medicinal chemistry. A variety of pharmacological properties of pyrazolines is associated with the nature and position of various substituents, which is especially evident in diarylpyrazolines. Compounds with a chalcone fragment show a wide range of biological properties as well as high reactivity which is primarily due to the presence of an α, β-unsaturated carbonyl system. At the same time, bicyclic monoterpenoids deserve special attention as a source of a key structural block or as one of the pharmacophore components of biologically active molecules. A series of new diarylpyrazoline derivatives based on isobornylchalcones with different substitutes (MeO, Hal, NO₂, N(Me)₂) was synthesized. Antioxidant properties of the obtained compounds were comparatively evaluated using in vitro model Fe²⁺/ascorbate-initiated lipid peroxidation in the substrate containing brain lipids of laboratory mice. It was demonstrated that the combination of the electron-donating group in the para-position of ring B and OH-group in the ring A in the structure of chalcone fragment provides significant antioxidant activity of synthesized diarylpyrazoline derivatives.     

Reactions of caryophyllene oxide with ethane-1,2-dithiol and 2-sulfanylethanol catalyzed by Lewis acids

Russian Journal of Organic Chemistry - Reactions of caryophyllene oxide with ethane-1,2-dithiol and 2-sulfanylethanol in the presence of Lewis acids (BF3 · Et2O and ZnCl2) as catalyst afforded...     

Synthesis of thiols from isobornylphenols

4-(3-Sulfanylpropyl)-2-isobornyl-6-methylphenol and 4-(sulfanylmethyl)-2,6-diisobornylphenol were synthesized from the corresponding 4-(bromoalkyl)phenols according to known procedures. Isobornylphenol with a trimethylene linker was converted into thiol by alkaline hydrolysis of thiouronium salt. The methylene-bridged analog was obtained by reduction of S-benzyl thioacetate with LiAlH₄.     

Reactions of terpene alcohols and diols with chlorine dioxide in dimethylformamide

The system chlorine dioxide–dimethylformamide in combination with or without a catalytic amount of MoCl₅, CeCl₃, ZrOCl₂, or VO(acac)₂ induces oxidative chlorination of a number of bicyclic terpene alcohols and vicinal diols. 2α-Chloropinan-3-one, 3α-chloro-10β-pinan-4-one, 5α-chloro-3α-hydroxycaran-4-one, 5β-chloro-3β-hydroxycaran-4-one, and 4α-chloro-2α-hydroxypinan-3-one were thus synthesized in good preparative yields.     

Synthesis and membrane protective activity of 4-alkoxymethyl-2,6-diisobornylphenols

Bromination of 2,6-diisobornyl-4-methylphenol gave the corresponding 4-bromomethyl derivative, whose reaction with alcohols resulted in 4-alkoxymethyl-2,6-diisobornylphenols. Their toxicity, membrane protective and antioxidant activity were tested using red blood cells of laboratory mice. The synthesized compounds do not exhibit cytotoxicity at the concentrations of 10 and 100 μmol L^–1 and are characterized by high membrane protective and antioxidant activity in the concentrations of 1 and 10 μmol L^–1.