Rearrangement of thiazolidine derivatives - a synthesis of a chiral fused oxathiane-γ-lactam bicyclic system.

Reaction of L-cysteine with carbonyl compounds leads to thiazolidine derivatives which undergo a stereoselective conversion to two types of chiral bicyclic products bearing two or three stereogenic centers, including the first fused oxathiane-γ-lactam system.

Chiral 2-azabicycloalkanes bearing 1,2,3-triazole, thiourea, and ebselen moieties - Synthesis and biological activity.

2-Azabicycloalkanes: 2-azabicyclo[2.2.1]heptane and 2-azabicyclo[3.2.1]octane were used as a chiral platform for the construction of a set of 1,2,3-triazole, thiourea, and ebselen derivatives. Cytotoxicity and antiviral activity studies revealed the most promising potency for selected thioureas.

Novel inhibitors of HSV-1 protease effective in vitro and in vivo.

Herpes simplex virus type 1 (HSV-1) is a widespread human pathogen known to cause infections of diverse severity, ranging from mild ulceration of mucosal and dermal tissues to life-threatening viral encephalitis. In most cases, standard treatment with acyclovir is sufficient to manage the disease progression. However, the emergence of ACV-resistant strains drives the need for new therapeutics and molecular targets. HSV-1 VP24 is a protease indispensable for the assembly of mature virions and, as such, constitutes an interesting target for the therapy. In this study, we present novel compounds, KI207M and EWDI/39/55BF, that block the activity of VP24 protease and consequently inhibit HSV-1 infection in vitro and in vivo. The inhibitors were shown to prevent the egress of viral capsids from the cell nucleus and suppress the cell-to-cell spread of the infection. They were also proven effective against ACV-resistant HSV-1 strains. Considering their low toxicity and high antiviral potency, the novel VP24 inhibitors could provide an alternative for treating ACV-resistant infections or a drug to be used in combined, highly effective therapy.

Chiral sulfonamides with various N-heterocyclic and aromatic units - Synthesis and antiviral activity evaluation.

Chiral sulfonamides with aromatic fragments are important chemical building blocks found widely in many natural products, catalysts, and molecules of biological importance. In this report, we describe the efficient synthesis of a series of chiral sulfonamides which, in addition to the aromatic part (phenyl, biphenyl, and dansyl units), possess N-heterocyclic systems. The described compounds were obtained by nucleophilic substitution of chiral N-heterocyclic amines and commercially available aromatic sulfonyl chlorides under mild conditions. All derivatives were examined in antiviral assay against AdV5, HSV-1, HPIV-3, HCMV, and EMCV viruses.

Synthesis and Applications of Carbohydrate-Based Organocatalysts.

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.

Application of Polyamines and Amino Acid Derivatives Based on 2-Azabicycloalkane Backbone in Enantioselective Aldol Reaction.

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%).

Biaryl Sulfonamides Based on the 2-Azabicycloalkane Skeleton-Synthesis and Antiproliferative Activity.

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.

Synthesis and Cytotoxic Activity of Chiral Sulfonamides Based on the 2-Azabicycloalkane Skeleton.

A series of chiral sulfonamides containing the 2-azabicycloalkane scaffold were prepared from aza-Diels-Alder cycloadducts through their conversion to amines based on 2-azanorbornane or the bridged azepane skeleton, followed by the reaction with sulfonyl chlorides. The cytotoxic activity of the obtained bicyclic derivatives was evaluated using human hepatocellular carcinoma (HCC), medulloblastoma (MB), and glioblastoma (GBM) cell lines. Chosen compounds were shown to notably reduce cell viability as compared to nonmalignant cells.

Chiral Thioureas-Preparation and Significance in Asymmetric Synthesis and Medicinal Chemistry.

For almost 20 years, thioureas have been experiencing a renaissance of interest with the emerged development of asymmetric organocatalysts. Due to their relatively high acidity and strong hydrogen bond donor capability, they differ significantly from ureas and offer, appropriately modified, great potential as organocatalysts, chelators, drug candidates, etc. The review focuses on the family of chiral thioureas, presenting an overview of the current state of knowledge on their synthesis and selected applications in stereoselective synthesis and drug development.