A flexible route for the stereoselective synthesis of a variety of 3-aryl dihydroisoquinolones and tetrahydroisoquinolines has been developed. The key step is a diastereoselective photoinduced 6π-electrocyclic ring closure of enantiopure aromatic enehydrazides via a 1,4-remote asymmetric induction. N-N bond cleavage to release the chiral appendage from the preliminary annulated compounds and/or concomitant reduction of the lactam carbonyl group completed the synthesis of the title compounds.

Chiral azaheterocycles substituted a to nitrogen represent the core unit of a wide range of alkaloids and biologically active compounds. They also play an important role as key targets for the pharmaceutical industry. Consequently, the stereocontrol of carbon centers embedded in these azaheterocycles is a permanent synthetic task for organic chemists. In this regard, we have developed an alternative and conceptually new synthetic approach to a variety of 2-heteroaryl cyclic amines and 6-aryl piperidin-2-ones which is based upon the asymmetric reduction of chiral endocyclic enenydrazides bearing a (S)-methylprolinol chiral auxiliary (SMP). This new synthetic methodology has then been illustrated by the total synthesis of S-(‑)-Anabasine and the stereoselective synthesis of cis-2,6-diarylated piperidines in high yields and high level of enantioselectivity.

Layered double hydroxides (LDHs), have attracted attentions because of their layered structure and high anion-exchange capacity [1]. Positively charged brucite-like layers with interlayer spaces containing anions and water molecules form LDHs structure. Overall structure of LDHs makes it suitable as a heterogeneous catalyst for organic reactions [2-3].Strecker reaction is an important process in α-aminonitriles synthesis. α-Aminonitriles play key roles in pharmaceutical industry, especially in preparation of α-amino acid and the various nitrogen and sulfur containing heterocycles[4]. Mentioned reaction can be mediated by homogenous catalysts with high yields. Although homogenous catalysts are highly efficient, they are expensive, toxic and need tedious work up. So heterogeneous catalysts such as molecular sieves, natural polymers, nano-sized materials and metal organic frameworks are some promising alternatives for this three-component reaction [5]. In this study, we used LDH as a heterogeneous catalyst for Strecker reaction, which resulted in high yields and short reaction time.

A five-step synthesis of 4-(1-mesyloxyethyl)-6-methyl-5-tosyl-1,2,3,4-tetrahydropyrimidin-2-one via amidoalkylation has been developed. Reaction of this compound with C-, O-, S-, and N-nucleophiles led to the highly diastereoselective formation of polysubstituted 2,3,4,5-tetrahydro-1H-1,3-diazepin-2-ones as a result of ring expansion. The diastereoselectivity of the reaction depended on the nucleophile used and changed from cis to trans. The results obtained were explained by the formation of a bicyclic cyclopropane intermediate followed by cleavage of the zero bridge and stereoselective addition of the nucleophile to the resulting dihydro-1H-1,3-diazepin-2-one under kinetic control. The prepared cis-4-alkoxy-5-methyldiazepines reacted with alcohols under acidic conditions to give thermodynamically more stable trans-isomers.

Amidoethyl-p-benzoquinones are easily accessible from 2,5-dimethoxybenzaldehyde. A one-step Wittig-hydrolysis reaction is followed by an amidation of the produced 2,5-dimethoxycinnamic acid. Hydrogenation and oxidative demethylation complete the sequence to the respective amidoethyl-p-benzoquinones. The spectroscopic data of the products is discussed.

NaBH4, CH3CO2H, Pd/C has been described as a reagent system to hydrogenate alkenoates and alkenones. Here, we show that O-debenzylation does not occur under the conditions, making it possible to hydrogenate a double bond under Pd/C catalysis without O-debenzylation or N-debenzylation.

The photochemistry of the vinyl substituted (E)-3-(anthran-9-yl)propenoates and (E)-9-(aroylethenyl)anthracenes as well of their reduced derivatives has been studied at lambda = 254 nm and at lambda= 352 nm. At lambda = 254 nm and lambda= 352 nm, the 9-vinyl substituted anthracenes undergo E/Z-isomerization, while their reduced derivatives undergo [4+4]-dimerisation reactions at lamda = 352 nm. An X-ray crystal structure shows the [4+4]-photoadducts to be head-to-tail. The photochemistry of cycloadducts of (E)-3-(anthran-9-yl)propenoates and (E)-9-(aroylethenyl)anthracenes with maleimides and other activated dienophiles show a number of reactions, among them retro-cleavage of the cycloadducts to the respective anthracenes.

η⁶-Dihydronaphthalene tricarbonylchromium(0) complexes and η⁶-indene tricarbonylchromium(0) have been prepared and subjected to Pd(0) catalysed reactions with iodoarenes. The reaction of η⁶-dihydronaphthalene tricarbonylchromium(0) complexes with iodoarenes under Jeffery conditions leads after decomplexation to triarylated products. The stereo- and regiochemistry of these products could be affirmed by an X-ray crystal structure. The η⁶-dihydronaphthalene unit can be part of more complicated structures such as of estrone derived compounds without changing the course of the reaction. The reaction of η⁶-indene tricarbonylchromium(0) with iodoarenes, however, leads to benzophenones, where the indene unit is not incorporated.

Influence of reagent ratio on the composition of products of the reaction between 1,1,2,2-tetrabromoethane and imidazole or 1,2,4-triazole in a superbasic medium (potassium hydroxide – dimethyl sulfoxide) was investigated using GC/MS technique. It was found that nucleophilic substitution reaction is always accompanied by elimination reactions (dehydrobromation and debromation). In addition to 1,1,2,2-tetra(azol-1-yl)ethane, 1,1,2-tri(azol-1-yl)ethenes and 1,2-di(azol-1-yl)ethenes, as well as 1,2-di(azol-1-yl)-1-bromoethenes were detected. Reaction pathway that explains the formation of all major products was proposed.

N-Substituted benzisoselenazol-3(2H)-ones are well known for their ability to mimic the activity of an important antioxidant enzyme glutathione peroxidase. They eliminate the excess of reactive oxygen and nitrogen species and restore the cells redox homeostasis. In the catalytic cycle they can be easily transformed to diselenides, which also exhibit these unique properties. In this work, we have synthetized a series of N-alkyl benzisoselenazolones and corresponding diselenides. The antioxidant activity of all obtained compounds was evaluated and compared. The connection between the antioxidant properties and the ability to inhibit cancer cells proliferation was evaluated by a cytotoxic activity assay using PC-3 and DU145 cell lines.