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Synthetically challenging spirolactams were developed in good yields and regio-selectivity through a step-up oxidative dearomatization of easily accessible arenols tethered to esters in the presence of quaternary ammonium tribromide as an economic oxidant and amines. The reaction mechanism associated with this unprecedented dearomative lactamisation has been forecasted with a series of controlled experiments and DFT studies. [ABSTRACT FROM AUTHOR]

We solve the Schrödinger equation from first principles to investigate the many-body effects in the expansion dynamics of one-dimensional repulsively interacting bosons released from a harmonic trap. We utilize the multiconfigurational time-dependent Hartree method for bosons (MCTDHB) to solve the many-body Schrödinger equation at high level of accuracy. The MCTDHB basis sets are explicitly time-dependent and optimised by variational principle. We probe the expansion dynamics by three key measures; time evolution of one-, two- and three-body densities. We observe when the mean-field theory results to unimodal expansion, the many-body calculation exhibits trimodal expansion dynamics. The many-body features how the initially fragmented bosons independently spreads out with time whereas the mean-field pictures the expansion of the whole cloud. We also present the three different time scale of dynamics of the inner core, outer core and the cloud as a whole. We analyze the key role played by the dynamical fragmentation during expansion. A Strong evidence of the many-body effects is presented in the dynamics of two- and three-body densities which exhibit correlation hole and pronounced delocalization effect.

We conceptualized a radical cyclization approach for the synthesis of SCF3, SAr, SO2Ar and COAr featured spirocyclic [4.5] and [5.5] trienone between biaryls and ArSO2H or ArCOCO2H in presence of RFTA as a photocatalyst whereas the insertion of ArSSAr or AgSCF3 devoid of photocatalyst via an energetically demanding dearomative transformation under visible‐light catalysis. The photo‐excited charge transfer complex with biaryl tethered ynones provides a way to promote S‐centered radical generation followed by its insertion to enable a wide range of biologically important molecules. [ABSTRACT FROM AUTHOR]

A new one‐pot oxidative cleavage of C(sp2)−C(sp3) bond has been explored using two complementary protocols employing Phenylselenyl bromide (PhSeBr) as well as Phenyltrimethylammonium Tribromide (PTAB), with much greater efficiency and scope. The oxidative cleavage proceeds via a dearomatization step to afford potentially useful bromonaphthols along with corresponding aldehydes. In this course, we also described the first synthesis of synthetically important azido‐halo naphthaleneones. [ABSTRACT FROM AUTHOR]

Xyloketals, unique bioactive compounds, isolated from mangrove fungus Xylaria sp. (no. 2508), having multiple pharmacological, therapeutic properties, have prompted enormous research on their stereochemistry, bioactivity and synthetic attempts made toward this novel family. This review brings forward a systematic and comprehensive survey of the method of both racemic and enantioselective synthesis, reactivity, and biological properties associated with the xyloketal derivatives and their analogues. [ABSTRACT FROM AUTHOR]

Premature loss of primary teeth associated with a parafunctional habit in 30-month-old child is re-ported. Report details, clinically and radiographical-ly, these effects in a very young child and reviews di-agnostic possibilities. Early detection and scrutiny by the pediatric dentist is important to determine origin and to rule out periodontal disease as manifestation of underlying systemic disease. [ABSTRACT FROM AUTHOR]

Sulfinyls are valuable structural moieties used for developing synthetically new pharmaceuticals and agrochemicals. Herein, we disclose a straightforward synthesis of sulfinylated spiro[5.5]trienones proceeding via an unprecedented BF 3 ·Et 2 O-promoted spirocyclization of biaryl ynones. The availability of relatively inexpensive BF 3 ·Et 2 O to carry out transformations on a bulk scale along with its further application towards the synthesis of dibenzocyclohepten-5-ones delivers a unique opportunity to deploy it in various synthetic directions.

Premature loss of primary teeth associated with a parafunctional habit in a 30-month-old child is reported. Report details, clinically and radiographically, these effects in a very young child and reviews diagnostic possibilities. Early detection and scrutiny by the pediatric dentist is important to determine origin and to rule out periodontal disease as a manifestation of underlying systemic disease.