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The manuscript describes a synthetic route for the formation of 5‐(methylisoindole‐1,3‐dione) pyrimidinones by [4+2] cycloaddition reactions of functionalized 1,3‐diazabuta‐1,3‐dienes with 2‐(3‐Oxo‐allyl)‐isoindole‐1,3‐dione generated in situ from phthaloylalanine and tosyl chloride using triethylamine as a base. The functionalized 5‐(methylisoindole‐1,3‐dione) pyrimidinones were further explored in the deprotection of amines to afford a variety of 5‐methylamino pyrimidinones. The synthesis of such functionalized pyrimidinones is significant as they have a wide range of pharmacological profiles and are valuable as organic synthons. Mechanistic insights are also proposed for the given synthetic methodology. [ABSTRACT FROM AUTHOR]

The functionalization of β-lactams at C-3 position are useful for the strategic improvement in both the dimensions, namely synthetic utility, as versatile intermediate in organic synthesis and biological potential of these heterocyclic systems. The present manuscript involved the π-facial selective synthesis β-lactam hybrids employing highly regioselective and diastereoselective Oxo-Diels-Alder reaction of diethyl ketomalonate with α-dienyl-β-lactam with stereocentres at its α- and β-positions. This protocol provided the cycloaddition of α- and β-stereocentric diene with symmetrical heterodienophiles forming biologically potent regioselective and diastereoselective α-lactams substituted pyrano bifunctional hybrids in good yields and β-facially selectivity. [ABSTRACT FROM AUTHOR]

3-Butadienyl-β-lactams are useful organic synthon which have efficiently been explored for the synthesis of a variety of heterocyclic systems. The present review compiles the various reports on the synthesis of 3-butadienyl-β-lactams and their explorations in the development of variety of monocyclic as well as condensed heterocyclic systems. [ABSTRACT FROM AUTHOR]

The manuscript describes a facile and highly diastereoselective synthesis of cis-3-(hydroxy/bromo)methyl-1-aryl-4-(-styryl)azetidin-2-ones via copper(i) mediated Kinugasa reactions of previously unexplored functionalized α,β-unsaturated nitrones. A variety of functionalized acetylenes and α,β-unsaturated nitrones were studied to yield cis-3-(hydroxy/bromo)methyl-1-aryl-4-(-styryl)azetidin-2-ones in good yields (82%). [ABSTRACT FROM AUTHOR]

The reactions of butadienylketene with variety of 1,4-diazabuta-1,3-dienes are studied. The reactions resulted in the formation of previously unknown functionalized cis butadienyl-4-iminomethyl-azetidin-2-ones and butenylidene-butadienyl-[2,2′-biazetidine]-4,4′- diones. Butadienyl ketene reacts in fashion with both iminic portion of 1,4- diazabuta-1,3-dienes and competitive [4+2] of 1,4-diazabuta-1,3-dienes as 4π component with butadienyl ketene as 2π component are not observed. [ABSTRACT FROM AUTHOR]

Highly diastereo- and π-facially selective imino Diels–Alder cycloadditions of 3-allylideneamino-2-azetidinones having stereocentres at its α- and β-positions, with symmetrical dienophiles leading to the formation of biologically potent (2-oxo-4-styrylazetidin-3-yl)–pyridine hybrids have been reported. [ABSTRACT FROM AUTHOR]

Abstract: The regioselective nitroso Diels–Alder (NDA) cycloadditions of 3-dienyl-2-azetidinones with nitrosobenzene to generate oxazine-substituted β-lactams in excellent yields are reported. The amidiolytic ring opening of the cycloadducts with sodium methoxide followed by iodocyclization using I2/K2CO3 etiquette to capitulate previously unknown, multisubstituted pyrroloxazine in outstanding yields is also accounted. [Copyright &y& Elsevier]

Polymeric membrane electrodes (PMEs) and coated graphite electrodes (CGEs) containing 1,3,4-trisubstituted-2-azetidinone derivatives as ion carriers are reported here for bismuth(III) ion selectivity. These electrodes exhibited Nernstian response for Bi3+ ions over a wide concentration range (5.0 × 10-7 M to 1.0 × 10-1 M for CGE) with a lower detection limit of 3.98 × 10-7 M (for CGE) and wide pH range (1.3-5.0). Compared to polymeric membrane electrode, the coated graphite electrode has shown better selectivity for Bi3+ ions with respect to common metal ions. Proposed electrodes have been used for the estimation of Bi3+ ions in pharmaceutical and glass samples. [ABSTRACT FROM AUTHOR]

Abstract: The regio-, diastereo-, and π-facial selective Lewis acid mediated Diels–Alder reactions of cis/trans-3-butadienyl-2-azetidinones with unsymmetrical dienophiles viz. methyl acrylate, dimethyl fumarate, and acrolein leading to the synthesis of diastereomerically pure and biologically potent 1,3,4-trisubstituted-2-azetidinones are reported. Theoretical calculations at HF/6-31G∗∗ and 6-31G∗∗/DFT levels have been performed to support the observed π-facial selectivity. The formation of diastereomerically pure ‘endo’ adducts is supported by the X-ray diffraction studies. [Copyright &y& Elsevier]

The chemo- as well as regioselective participation of N-aryl imines as 4π component in aza-Diels-Alder reactions with 3-butadienyl-2-azetidinones in the presence of Lewis acid catalysts resulting in novel quinoline derivatives is described. [ABSTRACT FROM AUTHOR]

Abstract: The present Letter describes the use of β-lactams for the synthesis of functionalized β-amino esters and their transformation to trisubstituted octahydroisoquinolone derivatives in good yields with an extension to their one-pot synthesis. [Copyright &y& Elsevier]

Abstract: A convenient and unprecedented synthesis of functionally enriched octahydroindole-based scaffolds has been developed via inter- and intra-molecular amidolysis of C-3 functionalized β-lactams. The cytotoxic evaluation on oesophageal cancer cell line WHCO1 has revealed 7d as the most potent of the test compounds exhibiting an IC50 value of 12.97μM. The developed strategy further assumes significance as it entails the preparation of highly functionalized indoles without the aid of transition metal catalysis or pre-functionalization of substrates. [Copyright &y& Elsevier]

Abstract: Assisted by PASS predictions, the antidepressant activity of 1,3,4-trisubstituted monocyclic β-lactams in seasonal affective disorders is described. [Copyright &y& Elsevier]

Abstract: A metal-free diastereoselective synthesis of novel 4-halo-3,6-di-aryl-2,6-diaza-bicyclo[3.2.0]heptan-7-one by intramolecular endo-trig haloamination of 3-amino-2-azetidinone is reported. The amidiolytic ring opening of diaza-bicyclo[3.2.0]heptan-7-one with sodium methoxide provides an easy access to previously unknown 4-halo-3-aryl amino-pyrrolidine-2-carboxylic acid methyl esters in good yields. [Copyright &y& Elsevier]

An abstract of the article "Tandem Aza-Michael and Intramolecular Amidic Ring-Opening Reactions of β-Lactams: A Facile Synthesis of 4-Oxo-4,5-dihydro-1H-pyrroles from β-Lactam Synthons" by Priyanka Sharma and colleagues is presented.

Intramolecular endo-trig haloamination of 3-amino-2-azetidinones provides diaza-bicycloheptanone derivatives. [ABSTRACT FROM AUTHOR]