Volume 52, Nº 12 (2016)

The complex of copper(II) trifluoromethanesulfonate with chiral isopropyl bis(oxazoline) ligand (i-Pr-Box) was immobilized on accessible and inexpensive Merrifield resin according to a “click” procedure. The resulting catalyst showed high efficiency and recyclability in the asymmetric Friedel–Crafts alkylation of indole and its derivatives. The catalyst can be recycled five times without appreciable loss in activity and enantioselectivity.

Allylation of the Favorsky reaction products with allyl halides under phase-transfer catalysis in the system CuI–K₂CO₃–Na₂SO₃–BTEAC–H₂O–C₆H₆ afforded the corresponding allylpropargyl alcohols in high yields (87–96%). The procedure is practical and scalable (more than 50 g of the target product can be prepared in a single run) and is characterized by high selectivity. Oxidation of secondary allylpropargyl alcohols with manganese dioxide in anhydrous acetonitrile at room temperature gave 75–81% of allylacetylenic ketones.

The addition of perfluoroalkanoic acids to 3-carene involves opening of the cyclopropane ring at the peripheral bonds with formation of a mixture of isomeric p-menth-1-en-8-yl and m-menth-1-en-8-yl perfluoroalkanoates. The reaction rate decreases as the length of the perfluoroalkyl radical of the acid increases. Trichloroacetic acid reacted with 3-carene at a lower rate than does trifluoroacetic acid, but the products are analogous p-menth-1-en-8-yl and m-menth-1-en-8-yl trichloroacetates.

The amination of butane-1,4-diol, isomeric dipropylene glycols, and cyclohexane-1,4-diyldimethanol in the presence of nickel/copper/chromium catalysts has been studied. The effect of the initial glycol structure on the reaction selectivity has been estimated.

Methyl (±)-(5Z,12E,14E)-9α-acetoxy-16-(3-chlorophenoxy)-15-deoxy-11-oxo-17,18,19,20-tetranorprosta- 5,12,14-trienoate was synthesized via selective protection/deprotection of the hydroxy groups in cloprostenol methyl ester, followed by oxidation of the C¹¹–OH group and DBU-promoted elimination of the 9-acetoxy group.

Substituted alkyl 4,5-dioxo-4,5-dihydro-1H-pyrrole-2-carboxylates reacted with urea to give alkyl 2-(carbamoylamino)-4-hydroxy-5-oxo-2,5-dihydro-1H-pyrrole-2-carboxylates which underwent intramolecular cyclization to 8-hydroxy-1,3,6-triazaspiro[4.4]non-8-ene-2,4,7-triones by the action of sodium methoxide.

Three-component condensation of methyl {4-[(2E)-3-(4-methoxyphenyl)prop-2-enoyl]phenyl}- carbamate with ninhydrin and L-proline in methanol–water (10: 1) afforded methyl {4-[1,3-dioxo-1′- (4-methoxyphenyl)-1,1′,2′,3,5′,6′,7′,7a′-octahydrospiro[indene-2,3′-pyrrolizin]-2′-ylcarbonyl]phenyl}carbamate. Heating of methyl {4-[(2E)-3-(4-methoxyphenyl)prop-2-enoyl]phenyl}carbamate with isatin and benzylamine in methanol gave methyl {4-[4′-(4-methoxyphenyl)-2-oxo-5′-phenyl-1,2-dihydrospiro[indole-3,2′-pyrrolidin]-3′-ylcarbonyl]phenyl}carbamate. The condensation of methyl {4-[(2E)-3-(4-methoxyphenyl)prop-2- enoyl]phenyl}carbamate with sarcosine and 11H-indeno[1,2-b]quinoxalin-11-one generated in situ from ninhydrin and o-phenylenediamine in boiling ethanol led to the formation of methyl {4-[4′-(4-methoxyphenyl)-1′-methyl-11,11a-dihydro-5aH-spiro[benzo[b]phenazine-6,2′-pyrrolidin]-3′-ylcarbonyl]phenyl}carbamate.

Due to intramolecular hydrogen bonding between the amino and nitro groups, o-nitroaniline is incapable of forming Schiff bases in the reactions with acetaldehyde and crotonaldehyde but is converted to quinoline derivative under Doebner–Miller reaction conditions via addition to the C=C double bond of the α,β-unsaturated aldehyde. Under analogous conditions, p-nitroaniline possessing a free amino group gives rise to the product of Doebner–Miller quinoline synthesis through intermediate formation of Schiff base dimer. The reaction of p-nitroaniline with benzaldehyde also yields the corresponding Schiff base, whereas o-nitroaniline is converted to N-benzyl derivative.

The reaction of a natural allylbenzene, myristicin, with nitriles afforded a series of 7,8-dihydro-[1,3]dioxolo[4,5-g]isoquinoline and 6,7-dihydro[1,3]dioxolo[4,5-h]isoquinoline derivatives.

Computer simulation at the PM7 level of theory of the structures of imidazo[4,5-c]pyridine derivatives (deaza analogs of purines) and their complexes with Aurora kinase A (AURKA) indicated prospects for their use as potential AURKA inhibitors in the treatment of oncological diseases. A number of new compounds of the selected imidazo[4,5-c]pyridine series, for which the highest inhibitory activity against AURKA was predicted, were synthesized in high yields for further biological testing.

DFT quantum chemical calculations with the Perdew–Burke–Ernzerhof (PBE) hybrid functional and triple-zeta (3ζ) basis set showed that the molecule of dimethyl ether encapsulated in model single-walled carbon nanotubes notably changes its structural and conformational parameters: the C–O bonds shorten, the COC bond angle increases, and new stable conformers nonexistent for the free ether appear. Decrease of the nanotube diameter is accompanied by increase of its force field effect on the encapsulated molecule.