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The global urge to adopt sustainable chemistry has resulted in the development of more environmentally benign strategies (EBS) that use CO2and CO2-derived chemicals in a step-economic manner. In this context, we investigated a dual C–H methylation and (C═O)-methoxylation of indole derivatives using dimethyl carbonate (DMC) in the presence of catalytic amounts of Cs2CO3. Mechanistic insights include DMF-assisted, DMC-induced cooperative ionic catalysis, which allows DMC to act as both a nucleophilic and an electrophilic precursor, resulting in (C═O)-methoxylation and C–H methylation of N-benzylindolyl ketones.

One of the main developments in unconventional superconductivity in the past two decades has been the discovery that most unconventional superconductors form phase diagrams that also contain other strongly correlated states. Many systems of interest are therefore close to more than one instability, and tuning between the resultant ordered phases is the subject of intense research1. In recent years, uniaxial pressure applied using piezoelectric-based devices has been shown to be a particularly versatile new method of tuning2,3, leading to experiments that have advanced our understanding of the fascinating unconventional superconductor Sr2RuO4(refs. 4–9). Here we map out its phase diagram using high-precision measurements of the elastocaloric effect in what we believe to be the first such study including both the normal and the superconducting states. We observe a strong entropy quench on entering the superconducting state, in excellent agreement with a model calculation for pairing at the Van Hove point, and obtain a quantitative estimate of the entropy change associated with entry to a magnetic state that is observed in proximity to the superconductivity. The phase diagram is intriguing both for its similarity to those seen in other families of unconventional superconductors and for extra features unique, so far, to Sr2RuO4.

Sr2RuO4has stood as the leading candidate for a spin-triplet superconductor for 26 years1. However, recent NMR experiments have cast doubt on this candidacy2,3and it is difficult to find a theory of superconductivity that is consistent with all experiments. The order parameter symmetry for this material therefore remains an open question. Symmetry-based experiments are needed that can rule out broad classes of possible superconducting order parameters. Here, we use resonant ultrasound spectroscopy to measure the entire symmetry-resolved elastic tensor of Sr2RuO4through the superconducting transition. We observe a thermodynamic discontinuity in the shear elastic modulus c66, which implies that the superconducting order parameter has two components. A two-component p-wave order parameter, such as px?+?ipy, naturally satisfies this requirement. As this order parameter appears to have been precluded by recent NMR experiments, we suggest that two other two-component order parameters, namely {dxz,dyz}and {dx2-y2,gxy(x2-y2)}, are now the prime candidates for the order parameter of Sr2RuO4.

Homoeopathy, being effective in various disease conditions, is a very popular choice of treatment among patients after conventional therapies. Despite that, the scientific community always tuned down its adoption due to the unexplored mechanism of action of homeopathic medicines. Unexplained working principles of Post-Avogadro dilutions and lack of molecular existence has always interfered with the acceptance of homoeopathy in the modern world. In the secondary action, homeopathic medicines show the reciprocal activity of its primary action. It seems that along with body homeostasis, it also acts on receptor level as an inverse agonist and after binding with a receptor at the resting phase it acts by reducing basal activity. As a result of this effect, it ends up producing an opposite biological effect known as a secondary action. Homeopathic drugs in its ultra–dilution probably show effects due to paradoxical activity which is generated at a definite time which can prove that secondary action is not due to the placebo effect. Paradoxical pharmacology clearly provides a basis for the concept of homeopathic drug dynamics as various drugs of modern medicines also have shown their paradoxical activity in high dilution. It is a complex receptor-mediated action which can alter the cell signaling pathway and can bring significant change in host adaptive response. In this review, we have exemplified the relation between the concepts of homeopathic drug dynamics with the rebound effect of drug substances to minimize the fallacy associated with homeopathic pharmacodynamics.