Zhendong Zhao

(E)-N'-(2-Hydroxy-benzyl-idene)-3,4,5-trimethoxy-benzohydrazide.

The title compound, C17H18N2O5, was synthesized from 3,4,5-trimethoxybenzohydrazide and 2-hydroxybenzaldehyde. The dihedral angle between the planes of the two benzene rings is 29.9 (2)°. The crystal structure involves intramolecular O—H⋯N, and intermolecular N—H⋯O and C—H⋯O hydrogen bonds.

Synthesis of a multifunctional hard monomer from rosin: the relationship of allyl structure in maleopimarate and UV-curing property

Rosin is an important forestry resource with a specific three-membered phenanthrene ring structure, which can improve the mechanical resistance of polymer coatings. In this paper, a high purity rosin monomer, tri-allyl maleopimarate containing three allyl groups has been synthesized. The yield of the monomer product was 93.2% with the purity of 96.1%. The structure of the synthesized monomer was characterized through gas chromatography (GC), mass spectrometry (MS), hydrogen nuclear magnetic resonance spectroscopy (1H NMR), carbon nuclear magnetic resonance spectroscopy (13C NMR) and elemental analysis. Additionally, we present new experimental results regarding the polymerization reaction under ultraviolet (UV) irradiation. The cured film of tri-allyl maleopimarate exhibited good mechanical properties. The films were also characterized through thermogravimetric (TG) and differential scanning calorimetry (DSC) analyses and a mechanism for polymerization was proposed. Overall, a facile catalytic process for the valorization of rosin in the field of UV polymerization is reported.

Skeletal rearrangement in the Ritter reaction of turpentine: A novel synthesis of p -menthane diamides

A novel skeletal rearrangement in the Ritter reaction was examined which conveniently generated p-menthane diamides from turpentine. A probable reaction mechanism was proposed based on employing thermodynamic analysis. All the products were purified and characterised by 1H NMR, IR, X-ray crystallography and ESI+-MS.

(E)-N′-(5-Bromo-2-hydroxy­benzyl­idene)-3,4,5-trimethoxy­benzohydrazide

The molecule of the title compound, C17H17BrN2O5, assumes an E configuration, with the 5-bromo-2-hydroxyphenyl and benzohydrazide units located on opposite sites of the C=N double bond. The dihedral angle between the planes of the two benzene rings is 32.48 (15)°. The crystal structure is stabilized by intramolecular O—H⋯N and intermolecular N—H⋯O hydrogen bonds.

Synthesis and Cytotoxic Activity of Amides from Isopimaric Acid

The amide derivatives were synthesized from isopimaric acid and characterized by spectroscopy. These amides were examined in vitro for their cytotoxic activity against four cancer cell lines. The majority of the screened compounds displayed better inhibitory activity than isopimaric acid, and many amides displayed promising cytotoxic activity against hepatocarcinoma (HepG-2), breast carcinoma (MDA-MB-231), and prostate adenocarcinoma (PC-3). It was found that the substituent type, number, and position in the benzene and heterocyclic rings have an important influence on cytotoxicity against the three tested cancer cell lines.

Facile synthesis of allyl resinate monomer in an aqueous solution under microwave irradiation

AbstractWe have developed a facile method for production of allyl resinate monomer (allyl rosin ester) via a phase transfer reaction under microwave irradiation. The synthesis of allyl resinate was conducted using allyl chloride and sodium resinate as starting materials in aqueous solution at 50° for 30 min with a yield of 94.7%, which is 20% higher than conventional heating method. The products precipitated spontaneously from the aqueous phase after reaction, which significantly facilitated the subsequent separation of monomer products. The synthesized monomer product appeared as a viscous liquid, with a viscosity of 460 mPa ⋅s at 25° and a density of 1.0469 g/cm3. The physical and chemical properties suggested that the synthesized monomer has great potential for free radical polymerization. Graphical AbstractA facile method for production of allyl resinate monomer via a phase transfer reaction was developed. Microwave irradiation could significantly improve the formation of allyl resinate monomer. The replacement of solvents with water has potential to reduce the production cost of the monomers.

1,4a,7-Trimethyl-7-vinyl-1,2,3,4,4a,4b,5,6,7,9,10,10a-dodeca-hydro-phenanthrene-1-carboxylic acid.

The title compound, pimaric acid, C20H30O2, was isolated from a mixture of resin acids. There are three rings in the structure. The two cyclohexane rings have classical chair conformations with trans-fused ring junctions. The cyclohexene ring appears as a semi-chair.

(E)-(4-Chloro­benzyl­idene){[(1R,4aS,10aR)-7-isopropyl-1,4a-dimethyl-1,2,3,4,4a,9,10,10a-octa­hydro-1-phenanthryl]­methyl}amine

The title compound, C27H34ClN, has been synthesized from 4-chlorobenzaldehyde and dehydroabietylamine. There are two unique molecules in the unit cell. Each molecule has three chiral centres, which exhibit R, S and R absolute configurations. The two cyclohexane rings form a trans ring junction with classical chair and half-chair conformations.