Mechanochemical synthesis and anticonvulsant activity of 3-aminopyrrolidine-2,5-dione derivatives.

A series of 3-aminopyrrolidine-2,5-dione derivatives was synthesized and tested for anticonvulsant activity. Succinimide derivatives were obtained from a simple solvent-based reaction and a mechanochemical aza-Michael reaction of maleimide or its N-substituted derivatives with selected amines. The structure of the compounds was confirmed by spectroscopic methods (NMR, FT-IR, HPLC, ESI-MS, EA and XRD for four compounds). The cytotoxic activity of the succinimide derivatives was evaluated using HepG2 cells for hepatocytotoxicity and SH-SY5Y cells for neurocytotoxicity. None of the studied compounds showed hepatocytotoxicity and two showed neurocytotoxicity. Initial anticonvulsant screening was performed in mice using the psychomotor seizure test (6 Hz, 32 mA). The selected compounds were evaluated in the following acute models of epilepsy: the maximal electroshock test, psychomotor seizure test (6 Hz, 44 mA), subcutaneous pentylenetetrazole seizure test, and acute neurotoxicity (rotarod test). The most active compound 3-((4-chlorophenyl)amino)pyrrolidine-2,5-dione revealed antiseizure activity in all seizure models (including pharmacoresistant seizures) and showed better median effective doses (ED50) and protective index values than the reference compound, ethosuximide. Furthermore, 3-(benzylamino)pyrrolidine-2,5-dione and 3-(phenylamino)pyrrolidine-2,5-dione exhibited antiseizure activity in the 6 Hz and MES tests, and 3-(butylamino)-1-phenylpyrrolidine-2,5-dione and 3-(benzylamino)-1-phenylpyrrolidine-2,5-dione exhibited antiseizure activity in the 6 Hz test. All active compounds demonstrated low in vivo neurotoxicity in the rotarod test and yielded favourable protective indices.

Comparison of Bioactive Secondary Metabolites and Cytotoxicity of Extracts from Inonotus obliquus Isolates from Different Host Species.

Inonotus obliquus, a wood-decaying mushroom, has been used as a health-promoting supplement and nutraceutical for centuries. It is a source of bioactive compounds accumulated in both the conks (pseudosclerotia/sclerotia) and the biomass obtained in vitro. This study aimed to qualitatively and quantitatively analyze the bioelements and selected metabolites produced in mycelial cultures obtained from different host species. The mycochemical potential of mycelial cultures isolated from pseudosclerotia grown in Betula pendula, Alnus glutinosa, and Carpinus betulus was compared. Parent cultures were obtained in two types of medium (malt extract agar substrates without and with birch wood). Experimental cultures were developed in 2 L bioreactors for 10 days. The content of bioelements was determined using FAAS and FAES methods. Organic compounds were estimated using the RP-HPLC-DAD method. The cytotoxicity of the extracts was evaluated in human keratinocytes HaCaT, human skin fibroblasts BJ, human liver cancer HepG2, human melanoma A375, and mouse melanoma B16-F10. The extracts showed the presence of bioelements: sodium, potassium, magnesium, calcium, zinc, manganese, iron, and copper; phenolic acids: p-hydroxybenzoic, caffeic, p-coumaric, and protocatechuic; sterols: lanosterol, ergosterol, ergosterol peroxide; triterpene compounds: betulin, betulinic acid, inotodiol; indole compounds: L-tryptophan, tryptamine, 5-methyltryptamine, melatonin. The content of bioactive substances in the biomass was dependent on both the origin of the host species of the fungus isolate and the type of culture medium. Based on the results of this study, mycelial cultures can be proposed as a potential source of bioactive compounds and are promising naturally derived cytotoxic agents.

Bioactivity and Mycochemical Profile of Extracts from Mycelial Cultures of Ganoderma spp.

Fungal mycelium cultures are an alternative to natural sources in order to obtain valuable research materials. They also enable constant control and adaptation of the process, thereby leading to increased biomass growth and accumulation of bioactive metabolites. The present study aims to assess the biosynthetic potential of mycelial cultures of six Ganoderma species: G. adspersum, G. applanatum, G. carnosum, G. lucidum, G. pfeifferi, and G. resinaceum. The presence of phenolic acids, amino acids, indole compounds, sterols, and kojic acid in biomass extracts was determined by HPLC. The antioxidant and cytotoxic activities of the extracts and their effects on the inhibition of selected enzymes (tyrosinase and acetylcholinesterase) were also evaluated. The total content of phenolic acids in the extracts ranged from 5.8 (G. carnosum) to 114.07 mg/100 g dry weight (d.w.) (G. pfeifferi). The total content of indole compounds in the extracts ranged from 3.03 (G. carnosum) to 11.56 mg/100 g d.w. (G. lucidum) and that of ergosterol ranged from 28.15 (G. applanatum) to 74.78 mg/100 g d.w. (G. adspersum). Kojic acid was found in the extracts of G. applanatum and G. lucidum. The tested extracts showed significant antioxidant activity. The results suggest that the analyzed mycelial cultures are promising candidates for the development of new dietary supplements or pharmaceutical preparations.

The Involvement of Xanthone and (E)-Cinnamoyl Chromophores for the Design and Synthesis of Novel Sunscreening Agents.

Excessive UV exposure contributes to several pathological conditions like skin burns, erythema, premature skin aging, photodermatoses, immunosuppression, and skin carcinogenesis. Effective protection from UV radiation may be achieved with the use of sunscreens containing UV filters. Currently used UV filters are characterized by some limitations including systemic absorption, endocrine disruption, skin allergy induction, and cytotoxicity. In the research centers all over the world new molecules are developed to improve the safety, photostability, solubility, and absorption profile of new derivatives. In our study, we designed and synthesized seventeen novel molecules by combining in the structures two chromophores: xanthone and (E)-cinnamoyl moiety. The ultraviolet spectroscopic properties of the tested compounds were confirmed in chloroform solutions. They acted as UVB or UVA/UVB absorbers. The most promising compound 9 (6-methoxy-9-oxo-9H-xanthen-2-yl)methyl (E)-3-(2,4-dimethoxyphenyl)acrylate) absorbed UV radiation in the range 290-369 nm. Its photoprotective activity and functional photostability were further evaluated after wet milling and incorporation in the cream base. This tested formulation with compound 9 possessed very beneficial UV protection parameters (SPFin vitro of 19.69 ± 0.46 and UVA PF of 12.64 ± 0.32) which were similar as broad-spectrum UV filter tris-biphenyl triazine. Additionally, compound 9 was characterized by high values of critical wavelength (381 nm) and UVA/UVB ratio (0.830) thus it was a good candidate for broad-spectrum UV filter and it might protect skin against UVA-induced photoaging. Compound 9 were also shown to be photostable, non-cytotoxic at concentrations up to 50 µM when tested on five cell lines, and non-mutagenic in Ames test. It also possessed no estrogenic activity, according to the results of MCF-7 breast cancer model. Additionally, its favorable lipophilicity (miLogP = 5.62) does not predispose it to penetrate across the skin after topical application.

Photostability Testing of a Third-Generation Retinoid-Tazarotene in the Presence of UV Absorbers.

Exposure of a drug to UV irradiation could affect its physicochemical properties. Hence, photostability testing is essential for topically administered drugs. Tazarotene, a receptor-selective, third-generation retinoid, is commonly used to treat acne vulgaris and psoriasis. In the present study, an in-depth analysis of the photostability of tazarotene in ethanolic solution in the presence of zinc oxide and/or titanium dioxide as well as benzophenone-type UV filters was performed. Eleven presumed products were derived from the photocatalytic degradation of tazarotene using ultra-performance liquid chromatography-tandem mass spectrometry, and transformation pathways were proposed. The degradation process mainly affected the 4,4-dimethyl-3,4-dihydro-2H-thiopyran moiety. The fragments most susceptible to oxidation were the methyl groups and the sulfur atom. Moreover, in the presence of sulisobenzone, under UV irradiation, tazarotene was subjected to a degradation process, which resulted in two photodecomposition products. In silico studies performed by OSIRIS Property Explorer demonstrated that five of the degradation products could be harmful in terms of the reproductive effects, which are associated with 3,4-dihydro-6-methyl-2H-1-benzothiopyran 1,1-dioxide, while one of them demonstrated potential irritant activity. The cytotoxic properties of the degradation products of tazarotene were assessed by MTT assay on a panel of human adherent cancer cells. Time- and concentration-dependent growth inhibition was evidenced in ovary (A2780) and breast (MDA-MB-231) cancer cell lines. The potential implication of the outcomes of the present research requires further studies mainly concerning the photostability of tazarotene in the topical formulations.

S(+)-(2E)-N-(2-Hydroxypropyl)-3-Phenylprop-2-Enamide (KM-568): A Novel Cinnamamide Derivative with Anticonvulsant Activity in Animal Models of Seizures and Epilepsy.

Epilepsy is one of the most frequent neurological disorders affecting about 1% of the world's human population. Despite availability of multiple treatment options including antiseizure drugs, it is estimated that about 30% of seizures still remain resistant to pharmacotherapy. Searching for new antiseizure and antiepileptic agents constitutes an important issue within modern medicinal chemistry. Cinnamamide derivatives were identified in preclinical as well as clinical studies as important drug candidates for the treatment of epilepsy. The cinnamamide derivative presented here: S(+)-(2E)-N-(2-hydroxypropyl)-3-phenylprop-2-enamide (S(+)-N-(2-hydroxypropyl)cinnamamide, compound KM-568) showed anticonvulsant activity in several models of epilepsy and seizures in mice and rats. It was active in a genetic animal model of epilepsy (Frings audiogenic seizure-susceptible mouse model, ED50 = 13.21 mg/kg, i.p.), acute seizures induced electrically (maximal electroshock test ED50 = 44.46 mg/kg mice i.p., ED50 = 86.6 mg/kg mice p.o., ED50 = 27.58 mg/kg rats i.p., ED50 = 30.81 mg/kg rats p.o., 6-Hz psychomotor seizure model 32 mA ED50 = 71.55 mg/kg mice i.p., 44 mA ED50 = 114.4 mg/kg mice i.p.), chronic seizures induced electrically (corneal kindled mouse model ED50 = 79.17 mg/kg i.p., hippocampal kindled rat model ED50 = 24.21 mg/kg i.p., lamotrigine-resistant amygdala kindled seizure model in rats ED50 = 58.59 mg/kg i.p.), acute seizures induced chemically (subcutaneous metrazol seizure threshold test ED50 = 104.29 mg/kg mice i.p., ED50 = 107.27 mg/kg mice p.o., ED50 = 41.72 mg/kg rats i.p., seizures induced by picrotoxin in mice ED50 = 94.11 mg/kg i.p.) and the pilocarpine-induced status epilepticus model in rats (ED50 = 279.45 mg/kg i.p., ED97 = 498.2 mg/kg i.p.). The chemical structure of the compound including configuration of the chiral center was confirmed by NMR spectroscopy, LC/MS spectroscopy, elemental analysis, and crystallography. Compound KM-568 was identified as a moderately stable derivative in an in vitro mouse liver microsome system. According to the Ames microplate format mutagenicity assay performed, KM-568 was not a base substitution or frameshift mutagen. Cytotoxicity evaluation in two cell lines (HepG2 and H9c2) proved the safety of the compound in concentrations up to 100 µM. Based on the results of anticonvulsant activity and safety profile, S(+)-(2E)-N-(2-hydroxypropyl)-3-phenylprop-2-enamide could be proposed as a new lead compound for further preclinical studies on novel treatment options for epilepsy.

Discovery of Novel UV-Filters with Favorable Safety Profiles in the 5-Arylideneimidazolidine-2,4-dione Derivatives Group.

Effective protection from the harmful effects of UV radiation may be achieved by using sunscreens containing organic or inorganic UV filters. The number of currently available UV filters is limited and some of the allowed molecules possess limitations such as systemic absorption, endocrine disruption properties, contact and photocontact allergy induction, and low photostability. In the search for new organic UV filters we designed and synthesized a series consisting of 5-benzylidene and 5-(3-phenylprop-2-en-1-ylidene)imidazolidine-2,4-dione (hydantoin) derivatives. The photoprotective activity of the tested compounds was confirmed in methanol solutions and macrogol formulations. The most promising compounds possessed similar UV protection parameter values as selected commercially available UV filters. The compound diethyl 2,2'-((Z)-4-((E)-3-(4-methoxyphenyl)allylidene)-2,5-dioxoimidazolidine-1,3-diyl)diacetate (4g) was characterized as an especially efficient UVA photoprotective agent with a UVA PF of 6.83 ± 0.05 and favorable photostability. Diethyl 2,2'-((Z)-4-(4-methoxybenzylidene)-2,5-dioxo- imidazolidine-1,3-diyl)diacetate (3b) was the most promising UVB-filter, with a SPFin vitro of 3.07 ± 0.04 and very good solubility and photostability. The main photodegradation products were geometric isomers of the parent compounds. These compounds were also shown to be non-cytotoxic at concentrations up to 50 µM when tested on three types of human skin cells and possess no estrogenic activity, according to the results of a MCF-7 breast cancer model.