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Background: Vulvovaginal candidiasis is primarily caused by Candida albicans (C. albicans). Here, a novel organoselenium compound (G20) was synthesized and evaluated for anti-Candida activity. Methods: Growth-inhibition studies and medium acidification assays to assess the inhibition of the yeast plasma membrane H+-ATPase (Pma1p) were carried out in vitro using G20. A self-nanoemulsifying formulation (SNEP) of G20 was prepared and evaluated for antimycotic activity in a mouse model. Results: G20 inhibited the growth of C. albicans through a mechanism that, at least in part, involves the inhibition of Pma1p. The G20-SNEP formulation significantly reduced vaginal colonization and vaginal inflammation relative to yeast-infected but untreated control mice. Conclusion: G20-SNEP exhibits potent antimycotic activity in a mouse model of vulvovaginal candidiasis. [ABSTRACT FROM AUTHOR]

A mini-review presents advances in the application of graphene-based materials in catalytic stereoselective synthesis. Examples of chiral organocatalysts and metal complexes immobilized on carbon nanosheets are discussed. [ABSTRACT FROM AUTHOR]

This paper describes the synthesis of chiral diselenides based on 2-azabicycloalkane or the pyrrolidine skeleton using in situ generated Na2Se2 as an efficient selenylating reagent. All the diselenides were obtained in moderate yields under mild conditions. The well-defined enantio- and diastereomerically pure compounds were tested in the asymmetric alkoxyselenylation of alkenes yielding products with diastereoisomeric excess up to >99%. [ABSTRACT FROM AUTHOR]

Following recent experimental work demonstrating strong nonlinear optical properties, namely second harmonic generation of light, in crystals composed of 16,20-dinitro-(3,4,8,9)-dibenzo-2,7-dioxa-5,10-diaza[4.4.4]propellane molecules [A. Miniewicz, S. Bartkiewicz, E. Wojaczyńska, T. Galica, R. Zaleśny and R. Jakubas, J. Mater. Chem. C, 2019, 7, 1255–1262] in this paper we aim to investigate "structure–property" relationships for a series of 16 propellanes presenting a wide palette of substituents with varying electron-accepting/donating capabilities. To that end, we use electronic- and vibrational-structure theories and a recently developed generalized few-state model combined with a range-separated CAM-B3LYP functional to analyze electronic and vibrational contributions to the first hyperpolarizability for the whole series of molecules. The variations in computed properties are large among the studied set of substituents and can reach an order of magnitude. It has been demonstrated that the maximum values of frequency-independent first hyperpolarizability are expected for strong electron-accepting NO2 substituents, but only at the preferred position with respect to the electronegative oxygen atom in the 1,4-oxazine moiety. This holds for electronic as well as vibrational counterparts. [ABSTRACT FROM AUTHOR]

An efficient procedure for the synthesis of new enantiopure pyrrolidine-based sulfides bearing additional nitrogen donors and secondary amines based on a bicyclic 2-azanorbornane skeleton was developed. Their application as ligands in palladium-catalyzed Tsuji-Trost reactions led to high yields and up to 82% ee. [ABSTRACT FROM AUTHOR]

Chiral scaffolds of 2-azabicyclo[2.2.1]heptane and 2-azabicyclo[3.2.1]octane were used for the construction of new modular catalysts containing complexing moieties pyridine, 2,2′-bipyridine and 1,10-phenanthroline appended by an imine linkage. The coordination abilities of the new ligands towards Zn(ii) were investigated using NMR and UV spectroscopy. The plausible structures of the [ZnL2]2+ and [ZnLXn](2−n)+ complexes formed were established by comparison of the experimental and DFT-calculated NMR spectra. The catalytic application of the [ZnLXn](2−n)+-type complexes in the asymmetric aldol reaction of ketones with aromatic aldehydes produced an excess of the respective syn-aldols in up to ＞98% ee. [ABSTRACT FROM AUTHOR]

Enantiomerically pure bicyclic derivatives of 2-azanorbornane containing sulfonamide, amide, and thiourea functionalities were synthesized using aza-Diels-Alder reaction. [ABSTRACT FROM PUBLISHER]

Mannich-type reactions of a chiral bicyclic imine and various nucleophiles yield the corresponding adducts with good to high diastereoselectivity. The influence of the reaction conditions on the yield and stereochemical outcome is investigated. The configuration of the products is established by 1 H NMR spectroscopy, and the major isomers of two adducts are characterized by X-ray crystallography. [ABSTRACT FROM AUTHOR]

Novel enantiopure policyclic nitrogen heterocycles have been obtained in the diastereoselective aza-Diels-Alder or Mannich reaction of dienes with imine formed in situ from ethyl glyoxylate and (1R,2R)-diaminocyclohexane. [ABSTRACT FROM AUTHOR]

The article examines the chemical and biological methods of preparing nonceramic sulfoxides that were developed from 2000 to 2009. According to the authors, nonceramic sulfoxides are viewed as important and efficient in the field of asymmetric synthesis. The use of nonceramic sulfoxides as chiral auxiliaries and intermediates is proven by the high asymmetric induction used by a sulfinyl fragment and the stability of its configuration.

A chiral S, S-donating C2-symmetric ligand containing two stereogenic centers was prepared from rac-trans-1,2-cyclohexanediol. An effective deracemization of trans-1,2-bis(phenylsulfenyl)cyclohexane was achieved by the catalyzed enantioselective sulfoxidation, followed by the chromatographic separation of diastereomeric mono- and bis-sulfoxides. Subsequent recrystallization of enantiomerically enriched bissulfoxide and its final deoxygenation gave optically pure (1R,2R)-bis(phenylsulfenyl)cyclohexane. [ABSTRACT FROM AUTHOR]

Organocatalysis is a very useful tool for the asymmetric synthesis of biologically or pharmacologically active compounds because it avoids the use of noxious metals, which are difficult to eliminate from the target products. Moreover, in many cases, the organocatalysed reactions can be performed in benign solvents and do not require anhydrous conditions. It is well-known that most of the above-mentioned reactions are promoted by a simple aminoacid, l-proline, or, to a lesser extent, by the more complex cinchona alkaloids. However, during the past three decades, other enantiopure natural compounds, the carbohydrates, have been employed as organocatalysts. In the present exhaustive review, the detailed preparation of all the sugar-based organocatalysts as well as their catalytic properties are described. [ABSTRACT FROM AUTHOR]

Abstract: Chiral C 2-symmetric S,S- and Se,Se-donating ligands as well as the C 1 mixed S,Se-donating ligands were prepared from optically active 1,2-cyclohexanediol and 1,2-cyclopentanediol via the respective SN2 reactions. The bis(chalcogen) ligands obtained effectively catalyze the asymmetric allylic alkylation with enantioselectivities of up to 50% ee. [Copyright &y& Elsevier]

Carbon–carbon bond forming reactions, such as aldol reaction and condensation, belong to extremely desired transformations as manifested by >25,000 entries in SciFinder. Their stereoselective variant requires the use of an appropriate catalyst with a strictly defined structure. Hence, chiral 2-azabicycloalkane-based catalysts were designed, synthesized and tested in a stereoselective aldol reaction between cyclic/acyclic ketone and p-nitrobenzaldehyde both in organic and aqueous media. Among catalysts containing a chiral bicyclic backbone, amide based on 2-azabicyclo[3.2.1]octane and pyrrolidine units showed the best catalytic activity and afforded aldol product in excellent chemical yields (up to 95%) and good diastereo- and enantioselectivity (dr 22:78, ee up to 63%). [ABSTRACT FROM AUTHOR]

N-Heterocycles are considered as desirable scaffolds for the development of novel lead compounds for anticancer drug research. Among them, phosphorus-containing amino-derivatives play a crucial role. A series of imines and products of their further reactions with P-nucleophiles were obtained starting from vicinal bisamines. Reaction of ethylenediamine and α-carbonyl esters yielded in novel unexpected products, which structures were confirmed by crystallographic measurements. The cytotoxic activity evaluation was done on a variety of cell lines including HUH7, AKH12, DAOY, UW228-2, D283, D425, and U251. Human umbilical vein endothelial cells (HUVECs) were used as control. Two of the tested compounds, bearing TADDOL-derived, and trifluoromethyl substituents showed a significant effect on cell viability, though comparable to nonmalignant cells. [ABSTRACT FROM AUTHOR]

A library of 21 novel chiral 1,2,3-triazole-based 2-azabicycloalkane conjugates was designed and synthesized using the copper(I)-catalyzed click reaction. The obtained hybrids were assessed for their antiproliferative potency against three selected human cancer cell lines: Hs294T (melanoma), MIA PaCa-2 (pancreas tumor) and NCI-H1581 (lung tumor). The majority of the synthesized compounds demonstrated moderate to potent activity, and some of them appeared more selective than cisplatin, with selectivity index exceeding 9. [ABSTRACT FROM AUTHOR]

In a search for new, selective antitumor agents, we prepared a series of sulfonamides built on bicyclic scaffolds of 2-azabicyclo(2.2.1)heptane and 2-azabicyclo(3.2.1)octane. To this end, aza-Diels–Alder cycloadducts were converted into amines bearing 2-azanorbornane or a bridged azepane skeleton; their treatment with sulfonyl chlorides containing biaryl moieties led to the title compounds. The study of antiproliferative activity of the new agents showed that some of them inhibited the growth of chosen cell lines with the IC50 values comparable with cisplatin, and some derivatives were found considerably less toxic for nonmalignant cells. [ABSTRACT FROM AUTHOR]

In the search for new antitumor agents, aminophosphonic acids and their derivatives based on octahydroquinoxalin-2(1H)-one scaffold were obtained and their cytotoxic properties and a mechanism of action were evaluated. Phosphonic acid and phosphonate moieties increased the antiproliferative activity in comparison to phenolic Mannich bases previously reported. Most of the obtained compounds revealed a strong antiproliferative effect against leukemia cell line (MV-4-11) with simultaneous low cytotoxicity against normal cell line (mouse fibroblasts-BALB/3T3). The most active compound was diphenyl-[(1R,6R)-3-oxo-2,5-diazabicyclo[4.4.0]dec-4-yl]phosphonate. Preliminary evaluation of the mechanism of action showed the proapoptotic effect associated with caspase 3/7 induction. [ABSTRACT FROM AUTHOR]