N. P. Artemova

Study of “Racemic Compound-Like” Behavior of Diastereomeric Mixture of Pinanyl Sulfoxides by X-Ray Diffraction, IR Spectroscopy, and DFT Calculations

Abstract The oxidation of a β-hydroxysulfide in the pinane series by use of m-chloroperbenzoic acid resulted in the formation of the corresponding β-hydroxysulfoxide as a mixture of two diastereomers in 4:5 ratio. According to single-crystal X-ray diffraction (XRD) results, it is established that the diastereomeric mixture of sulfoxides crystallizes in the “racemic compound-like” manner under formation of asymmetric dimers through S=O··H–O interactions. This asymmetric dimer formed from diastereomeric molecules is a structural unit in both crystal modifications, the triclinic and the monoclinic one. The behavior of the diastereomeric mixture of pinane derived sulfoxides in crystals, melts and in tetrachloromethane solutions was studied by IR spectroscopy. The density functional theory (DFT) method with 6-31G (d, p) basis set was used to calculate the optimized geometrical parameters and vibrational frequencies of different associates in solutions. The calculated vibrational frequencies are compared with experimental IR spectra. GRAPHICAL ABSTRACT

Synthesis and antifungal activity of monoterpenoids of the carane series

The antifungal activity of terpenoids of the carane series was studied; an interaction was found between the structures of these compounds and their antifungal properties. The actions of several terpenoids on the adhesive activity and enzyme systems of the fungus Candida albicans were studied.

Antifungal activity of bicyclic monoterpenoids and terpenesulfides

A total of 33 compounds including bicyclic monoterpenes, oxides, allyl alcohols, and S-containing pinane and carane derivatives were screened for antifungal activity against mycelial and yeast-like fungi. The structure–activity relationship was studied. The most active antimycotics were found.

SULFUR-CONTAINING DERIVATIVES OF MONO- AND BICYCLIC NATURAL MONOTERPENOIDS

Examples of thiylation of natural mono- and bicyclic and variously functionalized monoterpenoids (alkenes, ketones, epoxides, alcohols) and the latest transformation pathways of the newly formed sulfur-containing derivatives were reviewed.

S=o…s=o Interactions as a Driving Force for Low-Temperature Conformational Rearrangement of Stable H-Bonding {S(O)-Ch2-Ch2-OH···}2 Synthon in two Modifications of Diastereomeric Pinanyl Sulfoxides Co-Crystal

GRAPHICAL ABSTRACT For the triclinic and monoclinic modifications of diastereomeric pinanyl sulfoxides co-crystal, remarkable alterations in unit cell parameters by transition from 293 to 150 К were ascertained. Such alterations are accompanied by conformational restructuring of a stable hydrogen-bonded synthon from an “unfolded” to a “folded” form. The driving force of this restructuring is the tendency to form S=O…S=O interactions, which show up in the low-temperature phases of both polymorphs. These are well-supported by the methods of quantum chemistry (DFT, B97-D/6-31G(d,p), AIM All).

Synthesis and anti-inflammatory and antipyretic activity of 2-(1′-hydroxy-4′-isopropenyl-1′-methylcyclohexyl-2′-thio)-methylethanoate

2-(1′-Hydroxy-4′-isopropenyl-1′-methylcyclohexyl-2′-thio)methylethanoate was synthesized via the reaction of (+)-1,2-limonene oxide with methylmercaptoacetate. The acute toxicity and anti-inflammatory and antipyretic activities of the starting compounds and the synthesized terpene sulfide were investigated.

SYNTHESIS OF PINENYLSULFIDES FROM cis-VERBENOL

The reaction of cis-verbenol with thiols in the presence of ZnCl2 occurred stereospecifically with substitution of the hydroxyl by a sulfide.

Synthesis of Sulfur-Containing Bis-Terpenoids Based on Monoterpene Oxides

Ethanedithiol and di(mercaptoethyl)sulfide react regio- and stereoselectively with (+)-3-carene and α-hydroxy(-)-β-pinene β-oxides in the presence of sodium ethoxide to give the corresponding bis- and tris-sulfides with two terpene fragments

Biological Activity of S-Containing Monoterpenoids

S-containing mono- and bicyclic monoterpenoids were reviewed with respect to antifungal, anti-inflammatory, anti-helicobacter, anticlotting, membrane-protective, antitumor, antimicrobial, antibacterial, antiparasitic, and antimalarial activity including establishment of structure–activity relationships.

Synthesis of S-containing derivatives of the sesquiterpene lactone britanin

The optimal method for isolating the sesquiterpene lactone britanin from the aerial part of Inula britannica L. (Asteraceae) was developed. Britanin was functionalized by reacting it with methyl mercaptoacetate.