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A new series of chiral 4,5-dihydro-1H-[1,2,4]-triazoline molecules, featuring a β-ᴅ-glucopyranoside appendage, were synthesized via a 1,3-dipolar cycloaddition reaction between various hydrazonyl chlorides and carbohydrate Schiff bases. The isolated enantiopure triazolines (8a–j) were identified through high-resolution mass spectrometry (HRMS) and vibrational spectroscopy. Subsequently, their solution structures were elucidated through NMR spectroscopic techniques. Single-crystal X-ray analysis of derivative 8b provided definitive evidence for the 3-D structure of this compound and revealed important intermolecular forces in the crystal lattice. Moreover, it confirmed the (S)-configuration at the newly generated stereo-center. Selected target compounds were investigated for anti-tumor activity in 60 cancer cell lines, with derivative 8c showing the highest potency, particularly against leukemia. Additionally, substituent-dependent anti-fungal and anti-bacterial behavior was observed. [ABSTRACT FROM AUTHOR]

A new series of chiral 4,5-dihydro-1H-[1,2,4]-triazoline molecules, featuring a β-ᴅ-glucopyranoside appendage, were synthesized via a 1,3-dipolar cycloaddition reaction between various hydrazonyl chlorides and carbohydrate Schiff bases. The isolated enantiopure triazolines (8a–j) were identified through high-resolution mass spectrometry (HRMS) and vibrational spectroscopy. Subsequently, their solution structures were elucidated through NMR spectroscopic techniques. Single-crystal X-ray analysis of derivative 8b provided definitive evidence for the 3-D structure of this compound and revealed important intermolecular forces in the crystal lattice. Moreover, it confirmed the (S)-configuration at the newly generated stereo-center. Selected target compounds were investigated for anti-tumor activity in 60 cancer cell lines, with derivative 8c showing the highest potency, particularly against leukemia. Additionally, substituent-dependent anti-fungal and anti-bacterial behavior was observed.

1,2,4-Triazole and 1,2,4-triazoline are important components of bioactive molecules and catalysts employed in organic synthesis. Therefore, the efficient synthesis of these components has received significant research attention. However, studies on their structural diversity remain lacking. Previously, we developed chiral phase-transfer-catalyzed asymmetric reactions of α-imino carbonyl compounds with α,β-unsaturated carbonyl compounds and haloalkanes. In this study, we demonstrate the formal [3 + 2] cycloaddition reaction of α-imino esters with azo compounds under Brønsted base catalysis, resulting in the corresponding 1,2,4-triazolines in high yields. The results revealed that a wide range of substrates and reactants can be applied, irrespective of their steric and electronic characteristics. The present reaction made the general preparation of 3-aryl pentasubstituted 1,2,4-triazolines possible for the first time. Furthermore, a mechanistic study suggested that the reaction proceeds without isomerization into the aldimine form. [ABSTRACT FROM AUTHOR]

1,2,4-Triazole and 1,2,4-triazoline are important components of bioactive molecules and catalysts employed in organic synthesis. Therefore, the efficient synthesis of these components has received significant research attention. However, studies on their structural diversity remain lacking. Previously, we developed chiral phase-transfer-catalyzed asymmetric reactions of α-imino carbonyl compounds with α,β-unsaturated carbonyl compounds and haloalkanes. In this study, we demonstrate the formal [3 + 2] cycloaddition reaction of α-imino esters with azo compounds under Brønsted base catalysis, resulting in the corresponding 1,2,4-triazolines in high yields. The results revealed that a wide range of substrates and reactants can be applied, irrespective of their steric and electronic characteristics. The present reaction made the general preparation of 3-aryl pentasubstituted 1,2,4-triazolines possible for the first time. Furthermore, a mechanistic study suggested that the reaction proceeds without isomerization into the aldimine form.

1,3-dipolar cycloaddition of diaryldiazomethanes Ar 2 C N 2 across Cl 3 C–CH N–CO 2 Et 1 yields Δ 3 -1,2,4-triazolines 2 . Thermolysis of 2 leads, via transient azomethine ylides 3 , to diaryldichloroazabutadienes [Ar(Ar')C N–CH CCl 2 ] 4 . Treatment of 4a (Ar = Ar' = C 6 H 5 ) and 4c (Ar = Ar' = p -ClC 6 H 4 ) with NaSR in DMF yields 2-azabutadienes [Ar 2 C N–C(H) C(SR) 2 ] 5 . In contrast, nucleophilic attack of NaS t Bu on 4 affords azadienic dithioethers [Ar 2 C N–C(S t Bu) C(H)(S t Bu)] ( 7a Ar = C 6 H 5 ; 7b Ar' = p -ClC 6 H 4 ). The reaction of 4a with NaSEt conducted in neat EtSH produces [Ph 2 C N–C(H)(SEt)–CCl 2 H] 8 , which after dehydrochloration by NaOMe and subsequent addition of NaSEt is converted to [Ph 2 C N–C(SEt) C(H)(SEt)] 7c . Upon the reaction of 4c with NaS i Pr, the intermediate dithioether [( p -ClC 6 H 4 ) 2 C N–CH C(S i Pr) 2 ] 5k is converted to tetrakisthioether [( p - i PrSC 6 H 4 ) 2 C N–CH C(S i Pr) 2 ] 6 . Treatment of 4a with the sodium salt of piperidine leads to [Ph 2 C N–CH C(NC 5 H 10 ) 2 ] 10 . The coordination of 6 on CuBr affords the macrocyclic dinuclear Cu(I) complex 11 . The crystal structures of 5i , 7a , b , 10 and 11 have been determined by X-ray diffraction. [ABSTRACT FROM AUTHOR]

Reactions of p-N-succinimidobenzoyl isothiocyanate (1) with different nucleophilic reagents afforded adducts. Simultaneous or subsequent cyclization of these adducts gave access to a variety of different heterocycles, including benzoxazole, quinazoline, pyrimidine, 1,2,4-triazoline, 1,3-thiazolidine and others. The structures of the new products were confirmed by their micro-analytical and spectral data. Supplemental materials are available for this article. Go to the publisher's online edition of Phosphorus, Sulfur, and Silicon and the Related Elements to view the free supplemental file. [ABSTRACT FROM AUTHOR]

2-Furoyl isothiocyanate (1) is used as a building block in synthesizing different heterocyclic systems of anticipated biological activities. Thus, isothiocyanate 1 was reacted with different nucleophilic reagents to produce five- and six-membered heterocyclic systems such as 1,2,4-triazoline, thiadiazolidine, quinazoline, benzothiazole, benzoxazole, benzimidazole, thiazolidine, and imidazolidine. The structures of all the synthesized compounds were confirmed by microanalytical and spectral data. The antimicrobial activity of some of the synthesized compounds was tested. Supplemental materials are available for this article. Go to the publisher's online edition of Phosphorus, Sulfur, and Silicon and the Related Elements to view the free supplemental file. [ABSTRACT FROM AUTHOR]

Condensation of galactaric acid bis hydrazide (1) with carbon disulfide in the presence of ethanolic potassium hydroxide gave the dipotassium salt of galactaric acid bis (hydrazidocarbodithioic acid) (2). Heterocyclization of the key compound 2 produced three different types of double headed acyclo C -nucleosides: acid-catalyzed dehydrative cyclization afforded the 5-thioxo-1,3,4-thiadiazoline 3, base-catalyzed dehydrosulfurative cyclization gave the 5-thioxo-1,3,4-oxadiazoline 5, and condensative cyclization with concomitant dehydrosulfuration and dehydration with different nitrogen nucleophiles yielded the 5-thioxo-1,2,4-triazolines 7 and 9a, b. Acetylation of the prepared acyclo C -nucleosides 3, 5, 7 and 9a, b with acetic anhydride in the presence of pyridine at ambient temperature caused acetylation of the sugar hydroxyls as well as heterocyclo imino protons to give the tetra- O -acetates 4, 6, and 10a, b, respectively. Representative members of the prepared compounds were tested for antimicrobial activity. [ABSTRACT FROM AUTHOR]