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New labdanoid derivatives containing hydrophilic substituents (amino, methylamino) in the C-4 position were synthesized via selective transformations of lambertianic acid chloride. A one-pot method was proposed to prepare 16-formyllambertianic acid amide and included selective formylation of lambertianic acid by POCl3 in DMF followed by amidation by aqueous NH4OH. The molecular structure of the compound was studied by an X-ray crystal structure analysis. Analgesic activity in a chemical irritation model was found for newly synthesized 4-amino-18-nor-15,16-epoxylabda-8(17),13,14-triene and 4-(pyrrolidin-1-yl)-18-nor-15,16-epoxylabda-8(17),13,14-triene oxalates and 16-hydroxymethyl)lambertianic acid amide.

In this paper, new thiazolidinones, thiazinanones, and thiazolidinediones based on a monoterpenoid (-)-campholenic aldehyde were synthesized and their antiulcer and anti-inflammatory activity was investigated. The thiazolidinones and thiazinanones containing a (-)-campholenic moiety have been shown to possess antiulcerogenic properties in indomethacin-induced ulcer test comparable to the activity of the reference drug omeprazole. None of the investigated thiazolidinediones showed antiulcerative activity in the test. One of the (-)-campholenic aldehyde-derived thiazolidinones has also demonstrated high anti-inflammatory activity on the histamine-induced inflammatory edema model similar to the activity of diclofenac. It is shown that changing a (-)-campholenic substituent for a linear aliphatic or a terpenic fragment with a pinane scaffold results in decreasing the pharmacological properties, though the (-)-campholenic moiety does not seem to make a key contribution to the pharmacological activity. Compounds 11 and 17 have been shown to exhibit antiulcer and anti-inflammatory action at a dose of 100 mg/kg.

New derivatives of isopimaric acid at the carboxylic acid were prepared. Their analgesic activity was studied in models of visceral and thermal pain. Isopimaric acid amides with aminoethanol and (2R)-(hydroxymethyl)pyrrolidine groups exhibited statistically significant analgesic activity in acetic acid-induced writhing (5 and 25 mg/kg doses) and hot-plate tests (25 mg/kg dose) that was comparable to that of diclofenac sodium (10 mg/kg dose). The new agents were characterized by low (LD50 > 1250 mg/kg) in vivo toxicity. Molecular modeling of possible interaction of the most active compounds with transmembrane G-protein-binding cannabinoid receptor CB2 was performed.

4-Ethoxycarbonyl(cyano)-1,3-dimethyl-β-carbolines were synthesized via thermolysis of 4-aryl-3(5)-azidopyridines and their optical and hypoglycemic properties were studied. For the first time, the accessible Hantzsch nitropyridines were used as the starting materials. Diazotization of 3-aminopyridines having a trimethoxyaryl substituent at the C-4 position of the pyridine ring by intramolecular azo coupling afforded 7,8,9-trimethoxy-2,4-dimethylpyrido[3,4-c]cinnolines. When evaluating the hypoglycemic properties of the four obtained β-carbolines, it was found that ethyl 7-fluoro-1,3-dimethyl-9H-pyrido[3,4-b]indole-4-carboxylate, the structure of which contains the fluorine atom, has the highest glucose-lowering action.

Phlomisoic acid reacted with methyl-1-deoxy-2,3,4-tri-O-acetyl-1-bromo-α-D-glucopyranuronate to form the 18-O-β-D-(glucuronopyranoside)-6′-O-methyl ester of 15,16-epoxylabda-8(9),13,14-triene. Reductive amination of methyl 16-formyl-15,16-epoxylabda-8(9),13,14-trienoate or this β-D-glucuronopyranoside of 16-formyl-15,16-epoxylabda-8(9),13,14-triene by propargylamine in the presence of NaBH4 gave the corresponding 16-propargylaminomethyl-15,16-epoxylabda-8(9),13,14-trienes. Copper-catalyzed azide-alkyne cycloaddition of the new terpenoid alkynes and the propargylamide of phlomisoic acid with methyl 1-deoxy-2,3,4-tri-O-acetyl-1-azido-α-D-glucopyranuronate synthesized the corresponding labdanoid glucuronides and diglucuronide. Selective screening of the labdanoid triazolylglucuronides identified compounds with analgesic activity in chemical and thermal irritation tests.

The Ritter reaction between monoterpenoid (–)-isopulegol and nitriles in the presence of concentrated sulfuric acid or trifluoromethanesulfonic acid yielded a series of chiral 1,3-oxazine derivatives. When studying the analgesic activity of the synthesized compounds in vivo, it was found that 1,3-oxazine synthesized by the reaction of (–)-isopulegol with benzyl cyanide increases the time of latency of the animal in the hot plate test of thermal pain irritation, not inferior in effectiveness to the comparison drug diclofenac sodium.

New structural analogs of 3-phenacyluridine were obtained as a result of N(3)-alkylation of 1-(2-acetoxyethyl)- and 1-(2-acetoxyethoxymethyl) uracil. Biological studies of the title compounds in an acute in vivo experiment did not reveal their hypnotic properties and ability to enhance the effects of diazepam and chloral hydrate.

The prostatotropic activity of glycyrrhizic acid disodium salt (Na2GA) was studied in the models of benign prostatic hyperplasia (BPH) induced by chronic injection of sulpiride (40 mg/kg intraperitoneally for 8 weeks) or testosterone propionate (20 mg/kg subcutaneously for 4 weeks) in the Wistar rats. The oral administration of Na2GA in a dose of 100 mg/kg produced a moderate antiproliferative effect in both BPH models resulting in reduced volume density of prostatic epithelium (in the testosterone model) and increased volume density of the glandular lumen (in both models). The observed prostatotropic effects of Na2GA were similar to those of Permixon and finasteride, but they were less pronounced as confirmed by smaller drops in epithelial volume density and epithelial-to-stromal ratio compared to the effects of both reference drugs.

Conjugates of terpenoids with 1,3,5-trisubstituted pyrazoles were synthesized by the cross-coupling of methyl 16-(2-chloro-2-oxoacetyl)labdatrienoate with terminal arylacetylenes via the Castro—Stephens reaction and heterocyclization of arylalkyne-1,2-diones with arylhydr-azines. The structure of one reaction product was established by X-ray diffraction. The conditions for the formation of furanolabdanoid arylalkyne-1,2-diones were found. The newly synthesized pyrazoles exhibit analgesic activity in a model of chemical irritation.

New hexahydro-2H-chromenes were synthesized by reactions of monoterpenoid (1R,2R,6S)-3-methyl-6-(prop-1-en-2-yl)cyclohex-3-ene-1,2-diol with aliphatic ketones in the presence of montmorillonite clay H+-K10. The compounds formed and isolated as a pair of diastereoisomers were evaluated for their analgesic activity in vivo. It was found that the analgesic activity of (4aR,8R,8aR)-4,7-dimethyl-3,4,4a,5,8,8a-hexahydrospiro[chromene-2,1ʹ-cyclohexane]-4,8-diol 8b significantly exceeds (two orders of magnitude higher) the activity of diclofenac sodium in the acetic acid-induced writhing test. It has low acute toxicity and is very promising for further development.

Nature methods 2020(17), 73–78 (2019). doi:10.1038/s41592-019-0628-z, The European XFEL (EuXFEL) is a 3.4-km long X-ray source, which produces femtosecond, ultrabrilliant and spatially coherent X-ray pulses at megahertz (MHz) repetition rates. This X-ray source has been designed to enable the observation of ultrafast processes with near-atomic spatial resolution. Time-resolved crystallographic investigations on biological macromolecules belong to an important class of experiments that explore fundamental and functional structural displacements in these molecules. Due to the unusual MHz X-ray pulse structure at the EuXFEL, these experiments are challenging. Here, we demonstrate how a biological reaction can be followed on ultrafast timescales at the EuXFEL. We investigate the picosecond time range in the photocycle of photoactive yellow protein (PYP) with MHz X-ray pulse rates. We show that difference electron density maps of excellent quality can be obtained. The results connect the previously explored femtosecond PYP dynamics to timescales accessible at synchrotrons. This opens the door to a wide range of time-resolved studies at the EuXFEL., Published by Nature Publishing Group, London [u.a.]

The paper describes the synthesis of new tetrahydroberberrubine derivatives containing polyfl uorophenyl- or alkylsulfonate groups at the O(9) position as well as those containing or not containing a bromine atom at the C(12) position. In a model of acute Triton-induced hyperlipidemia, tetrahydroberberrubine 9-O-(heptafluoro-4’-toluene)sulfonate was shown to reduce the cholesterol level by 23.5%, which is comparable with the eff ect of Simvastatin. At a concentration of 32 μg mL−1, tetrahydroberberrubine 9-O-pentafluorobenzenesulfonate inhibits the growth of the fungus Cryptococcus neoformans by 81.3±3.5%.

N-Heterocycle-containing (1S)-(+)-camphor-10-sulfonamide derivatives were synthesized. Their antiviral activity against the Ebola and Marburg viruses was estimated using a pseudovirus system based on the vesicular stomatitis virus. The derivatives bearing morpholine and triazole moieties demonstrated the highest inhibitory activity towards the Ebola virus glycoprotein. A moderate activity against the Marburg virus was found for a compound containing the piperidine moiety. A molecular modeling of the interaction between the synthesized derivatives and the binding site of glycoprotein of the Ebola virus was performed.

A series of compounds with a hydrogenated 2H-chromene skeleton was synthesized by the reaction of ketones and available para-menthane monoterpenoid (—)-isopulegol. A condensation product of (—)-isopulegol with the monoterpene ketone l-menthone was synthesized for the first time. The synthesized heterocycles were tested for analgesic activity and compounds with high analgesic activity in the in vivo tests were identified.

A series of 2,4,6-trisubstituted pyrimidines with antharanilic acid ester moiety have been designed and synthesized by employing a one-pot multicomponent approach from methyl 5-(ethynyl)anthranilate, aroyl or cinnamoyl chlorides and various amidines. All the compounds were evaluated for their cytotoxic activity with respect to model cancer cell lines (CEM-13, U-937, MDA-MB-231, BT-474, DU-145) using conventional MTT assays. Structure-activity relationship analysis revealed that 4,6-diarylpyrimidines 13–17, substituted with a pyridine or a pyrimidine ring in the 2 position displayed an increasing of activity compared to 2-methyl or 2-phenyl substituted pyrimidines. The 2-amino substututed compound 9 showed selectivity on the human monocyte-like cells U-937. Trisubstituted pyrimidines 18–21, containing a (E)-styryl substituent in the 6 position of the pyrimidine core, demonstrated an increasing of activity against the breast cancer cell lines MDA-MB-231, BT-474, and also against the human prostate cell lines DU-145. Compounds 18 and 20 shown the best potency towards the cancer cell lines MDA-MB-231; theirs activity was comparable with the activity of Doxorubicin on this cell lines. These compounds were confirmed to be cyclin-dependent kinase 9 (CDK9) inhibitors through in silico molecular modeling studies for the mode of action. The newly synthesized compounds may serve as lead molecules for the future research regarding the identification of new anticancer agents in the pyrimidine series.

The anti-inflammatory activity of tyrosol and 12 structural analogs including 3 new compounds was determined. Several structure-activity (anti-inflammatory) relationships were found. Adding a tert-butyl substituent to the aromatic ring and increasing the length of the alkyl chain decreased the anti-inflammatory activity. Pronounced antiulcer activity was found for p-tyrosol.

Conjugates of betulinic acid with 2-(fluoroacyl)cycloalkane-1,3-dione motifs were synthesized by reacting 3-chloro-2-(fluoroacyl)-2-cycloalkene-1-ones with an equivalent amount of betulinic acid aminoalkylamide hydrochlorides in the presence of Et3N in CHCl3. Reduction of betulonic acid conjugates with 2-trifluoroacetylcyclopentane-1,3-dione by NaBH4 in THF produced betulinic acid derivatives containing 2-(1-hydroxy-2,2,2-trifluoroethyl)cyclopentane-1,3-dione. The cytotoxicity of the synthesized compounds was assessed against glioblastoma multiforme (U-87 MG) and breast cancer cell lines (MCF7).

Antiulcerogenic activity of borneol and its N-heterocyclic esters was investigated using indomethacin-induced gastric ulcer model. A considerable antiulcerogenic effect comparable to that shown by Omeprazole and Famotidine was found for two investigated compounds in the indomethacin-induced gastric ulcer model. Bornyl 2-piperazinoacetate, with a non-substituted piperazine moiety, showed maximum antiulcerogenic activity in the indomethacininduced gastric ulcer model and demonstrated a significant gastroprotective effect in the ethanol-induced gastric ulcer model comparable to the effect of Omeprazole.