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Syed Ahmad uddin Gangvi was born in the village of Gangi (Mianwali).He was indeed a great scholar and a mystic of his time. He remained affiliated with Fiqh and its teachings effectively for a long period of 85 years. Being a scholar of such a status and magnitude Syed Ahmad served as the Great Mufti (Al Mufti al Azam) at Sial Shareef. He Authored books in Arabic, Persian, Urdu, Punjabi and Saraiki with equal skill and wisdom. Most of his works is available in manuscripts. All of his books reflect his scholarly wisdom and intellect and indicate his great achievements. Syed Ahmad uddin ranks as one of the greatest Jurists of Islamic civilization. During his lifetime he was acknowledged by the people as a jurist of the highest caliber. Outside of his scholarly achievements, he is popularly known amongst Muslims as a man of the highest personal qualities.

Developing a catalytic kinetic resolution (KR) protocol affording enantioenriched α-functionalized ketones with broad substrate scope and high efficiency has been a longstanding challenge. Here, we...

Organocatalyzed asymmetric Friedel–Craft reactions have enabled the rapid construction of chiral molecules with highly enantioselectivity enriching the toolbox of chemists for producing complex substances. Here, we report N-heterocyclic carbene-catalyzed asymmetric indole Friedel–Crafts alkylation-annulation with α,β-unsaturated acyl azolium as the key intermediate, affording a large variety of indole-fused polycyclic alkaloids with excellent diastereo- and enantioselectivities. The reaction mechanism is also investigated, and the reaction products can be easily converted to highly functionalized indole frameworks with different core structures. Indole-fused polycyclic alkaloids are present in numerous bioactive natural products. Here an enantioselective N-heterocyclic carbene-catalysed Friedel–Crafts alkylation/annulation cascade using acyl azolium salts as the electrophile provides access to these products with high stereoselectivity.

Invoked by the recent CMS observation regarding candidates of the χb(3P) multiplet, we analyze the hyperfine and mass splittings among the 3P multiplet in our unquenched quark model studies. The mass difference of χb2 and χb1 in the 3P multiplet measured by the CMS Collaboration (10.6±0.64±0.17 MeV) is very close to our theoretical prediction (12 MeV). Our corresponding mass splitting of χb1 and χb0 enables us to predict more precisely the mass of χb0(3P) to be (10490±3) MeV. Moreover, we predict ratios of the radiative decays of χbJ(nP) candidates, both in the unquenched quark model and quark potential model. Our predicted relative branching fraction of χb0(3P)→ϒ(3S)γ is one order of magnitude smaller than χb2(3P); this naturally explains the nonobservation of χb0(3P) in the recent CMS search. We hope these results provide useful references for forthcoming experimental searches.

We calculate the spectrum of $q\overline{q}c\overline{c}$ and $s\overline{s}c\overline{c}$ tetraquarks, where $q$, $s$, and $c$ stand for light ($u$, $d$), strange, and charm quarks, respectively, in a relativized diquark model, characterized by one-gluon-exchange plus confining potential. In the diquark model, a $q\overline{q}c\overline{c}$ ($s\overline{s}c\overline{c}$) tetraquark configuration is made up of a heavy-light diquark, $qc$ ($sc$), and anti-diquark, $\overline{q}\overline{c}$ ($\overline{s}\overline{c}$). According to our results, 13 charmonium-like observed states can be accommodated in the tetraquark picture, both in the hidden-charm ($q\overline{q}c\overline{c}$) and hidden-charm hidden-strange ($s\overline{s}c\overline{c}$) sectors.

Apart from its numerous biological activities like antidiabetic, anti-inflammatory, antimicrobial, pyrazine moiety plays an important role in luminescent materials. Its role in luminescent materials is due to its highly electron deficient nature specially when it is in the centre along the mainstay of extended π-conjugated systems. Similarly, new liquid crystalline compounds are being made constantly where the central benzoaromatic moiety is being replaced with the heterocycles including pyrazine due to their more variable nature. Pyrazine derivatives can also be used in supramolecular assemblies due to their efficient hydrogen bonding, protonation and complexation properties. Keeping in view the enormous applications of pyrazine derivatives we planned to synthesize new extended iminobenzoates with pyrazine moieties at the terminal positions. The planned iminobenzoates with terminal pyrazine moieties were prepared following standard procedures. The pyrazine-2-carbohydrazide (1) and 5-methylpyrazine-2-carbohydrazide (2) were prepared by refluxing their methyl esters with hydrazine hydrate in methanol. The esters (3a-3f) were synthesized by reacting 4-hydroxybenzaldehyde with differently substituted acid halides in tetrahydrofuran in the presence of triethyl amine. The target compounds that is, iminobenzoates with the pyrazine moieties at terminal positions (4a-4l), were obtained in good to excellent yields by the reaction of the hydrazides with the esters at reflux. The synthesized compounds were fully characterized using different spectroanalytical techniques including FT-IR, NMR, Mass, elemental analysis and single crystal X-ray diffraction analysis. The paper describes the synthesis of novel iminobenzoates following easy methods while utilizing commercially available starting materials. The synthesized iminobenzoates may possibly be converted to compounds with luminescent and liquid crystalline properties after making suitable changes to the pyrazine moieties. Properly substituted pyrazines on both sides, capable of further suitable extensions, may result in compounds with such properties.

We propose a new model to create a light meson in the heavy quarkonium transition, which is inspired by the Nambu--Jona-Lasinio (NJL) model. Hadronic transitions of ${J}^{PC}={1}^{\ensuremath{-}\ensuremath{-}}$ higher charmonia with the emission of an $\ensuremath{\eta}$ meson are studied in the framework of the proposed model. The model shows its potential to reproduce the observed decay widths and make predictions for the unobserved channels. We present our predictions for the decay width of $\mathrm{\ensuremath{\Psi}}\ensuremath{\rightarrow}J/\ensuremath{\psi}\ensuremath{\eta}$ and $\mathrm{\ensuremath{\Psi}}\ensuremath{\rightarrow}{h}_{c}(1P)\ensuremath{\eta}$, where $\mathrm{\ensuremath{\Psi}}$ are higher $S$ and $D$ wave vector charmonia, which provide useful references to search for higher charmonia and determine their properties in forthcoming experiments. The predicted branching fraction $\mathcal{B}(\ensuremath{\psi}(4415)\ensuremath{\rightarrow}{h}_{c}(1P)\ensuremath{\eta})=4.62\ifmmode\times\else\texttimes\fi{}{10}^{\ensuremath{-}4}$ is one order of magnitude smaller than the $J/\ensuremath{\psi}\ensuremath{\eta}$ channel. Estimates of partial decay width $\mathrm{\ensuremath{\Gamma}}(Y\ensuremath{\rightarrow}J/\ensuremath{\psi}\ensuremath{\eta})$ are given for $Y(4360)$, $Y(4390)$, and $Y(4660)$ by assuming them as $c\overline{c}$ bound states with quantum numbers ${3}^{3}{D}_{1}$, ${3}^{3}{D}_{1}$, and ${5}^{3}{S}_{1}$, respectively. Our results are in favor of these assignments for $Y(4360)$ and $Y(4660)$. The corresponding experimental data for these $Y$ states has large statistical errors which do not provide any constraint on the mixing angle if we introduce $S\ensuremath{-}D$ mixing. To identify $Y(4390)$, precise measurements on its hadronic branching fraction are required which are eagerly awaited from BESIII.

1,2-Dihydronaphthalenes are important molecules in both medicinal and synthetic chemistry, but methods for the catalytic asymmetric construction of this class of molecules are limited. The diastereo- and enantioselective N-heterocyclic carbene-catalyzed cascade annulation reactions using benzodiketones and enals under oxidative conditions, which afford a variety of 1,2-dihydronaphthalenes with two adjacent stereocenters in up to 99% yield, with >20:1 dr, and up to 99% ee, are reported. Furthermore, the product can be easily transformed to a series of useful compounds such as alcohol, amide, and epoxide.

We calculate the probabilities of various charmed meson molecules for $X(4260)$ under the framework of ${}^3P_0$ model. The results indicate that even though heavy quark spin symmetry forbids $S$ wave coupling of $D_1\bar{D}$ to the ${}^3S_1$ charmonia ($\psi(nS)$), the $D$ wave coupling is allowed and not negligible. Under this symmetry, the $D_1\bar{D}$ can couple to ${}^3D_1$ charmonia ($\psi(nD)$) via both $S$ and $D$ wave, and the overall coupling is around three times larger than that of $\psi(nS)$. The $X(4260)$ cannot be a pure molecule but a mixture of a charmonium and various charmed meson components. Since the $D_1\bar{D}$ couples strongly to $\psi(nD)$, our results suggest that in the $D_1\bar{D}$ molecular picture, the charmonium core of $X(4260)$ is $\psi(nD)$ instead of $\psi(nS)$. As a result, the experimental fact that the $R$ ratio has a dip around 4.26 GeV can be understood in the $D_1\bar{D}$ molecular picture of the $X(4260)$., Comment: 10 pages, 1 figure

We discuss the possible existence of the fully-heavy tetraquarks. We calculate the ground-state energy of the $bb \bar b \bar b$ bound state, where $b$ stands for the bottom quark, in a nonrelativistic effective field theory framework with one-gluon-exchange (OGE) color Coulomb interaction, and in a relativized diquark model characterized by OGE plus a confining potential. Our analysis advocates the existence of uni-flavor heavy four-quark bound states. The ground state $bb\bar b\bar b$ tetraquark mass is predicted to be $(18.72\pm0.02)$~GeV. Mass inequality relations among the lowest $QQ\bar{Q}\bar{Q}$ state, where $Q\in \{c, b\}$, and the corresponding heavy quarkonia are presented, which give the upper limit on the mass of ground state $QQ\bar{Q}\bar{Q}$. The possible decays of the lowest $bb\bar{b}\bar{b}$ are highlighted, which might provide useful references in the search for them in ongoing LHC experiments, and its width is estimated to be a few tens of MeV., Comment: Version accepted for publication in Eur. Phys. J. C

We study the excited $B$ mesons' contributions to the coupled-channel effects under the framework of ${}^3P_0$ model for the bottomonium. Contrary to what has been widely accepted, the contributions of $P$ wave $B$ mesons are generally the largest and this result is independent of the potential parameters to some extent. We also push the calculation beyond $B(1P)$ and carefully analyze the contributions of $B(2S)$. A form factor is a key ingredient to suppress the contributions of $B(2S)$ for low lying bottomonia. However, this suppression mechanism is not efficient for highly excited bottomonia such as $\Upsilon(5S)$ and $\Upsilon(6S)$. We give explanations why this difficulty happens to ${}^3P_0$ model and suggest analyzing flux-tube breaking model for the full calculation of coupled-channel effects., Comment: 15 pages, 6 figures

With Gaussian expansion method (GEM), realistic wave functions are used to calculate coupled-channel effects for the bottomonium under the framework of ${}^3P_0$ model. The simplicity and accuracy of GEM are explained. We calculate the mass shifts, probabilities of the $B$ meson continuum, $S-D$ mixing angles, strong and dielectric decay widths. Our calculation shows that both $S-D$ mixing and the $B$ meson continuum can contribute to the suppression of the vector meson's dielectric decay width. We suggest more precise measurements on the radiative decays of $\Upsilon(10580)$ and $\Upsilon(11020)$ to distinguish these two effects. The above quantities are also calculated with simple harmonic oscillator (SHO) wave function approximation for comparison. The deviation between GEM and SHO indicates that it is essential to treat the wave functions accurately for near threshold states., Comment: 21 pages, 6 figures, 6 tables

Hadronic transitions are important decay modes of heavy quarkonia and serve as an elegant probe for the internal structure. Several remarkable discoveries have been made to identify the conventional heavy quarkonia and to extract useful information about the so called “XYZ” exotic states. We studied the hadronic transitions of higher charmonia in the framework of our recently proposed effective model to create light meson(s) in heavy quarkonium transitions. In this contribution, we discuss our results for the charmonium-[Formula: see text] decays of higher [Formula: see text] and [Formula: see text] wave vector charmonia. We also discuss quantum number [Formula: see text] assignments for few experimentally observed charmoniumlike states.