N‐(6‐Bromo‐4‐oxo‐3,4‐di­hydro­pteridin‐2‐yl)‐2,2‐di­methyl­propan­amide

In the title compound, C₁₁H₁₂BrN₅O₂, the rings in the pterin moiety are planar. The carbonyl O atom is in a synperiplanar conformation, while the C—N—C(=O)—C linkage is antiperiplanar. N—H?N and N—H?O intermolecular hydrogen bonds transform the mol­ecules into infinite chains.     

Exact Risk Analysis of Wavelet Regression

Abstract

Wavelets have motivated development of a host of new ideas in nonparametric regression smoothing. Here we apply the too] of exact risk analysis, to understand the small sample behavior of wavelet estimators, and thus to check directly the conclusions suggested by asymptotics. Comparisons between some wavelet bases, and also between hard and soft thresholding, are given from several viewpoints. Our results provide insight as to why the viewpoints and conclusions of Donoho and Johnstone differ from those of Hall and Patil.     

Some properties of generalized intuitionistic fuzzy nilpotent matrices over distributive lattice

In this paper, the concept of lattice over generalized intuitionistic fuzzy matrices (GIFMs) are introduced and have shown that the set of GIFMs forms a distributive lattice. Some algebraic properties of generalized intuitionistic fuzzy matrices (GIFMs) are presented over distributive lattice. Also, some characteristics of generalized intuitionistic fuzzy nilpotent matrices (GIFNMs) are discussed over distributive lattice. Finally, the reduction of GIFNMs over distributive lattice are given with some properties.     

String-inspired Chern–Simons modified gravity in four dimensions

Field equations of the Chern–Simons modified gravity in four dimensions are obtained by a truncation of the field equations of the low energy effective string models with first order corrections in the string constant included.     

Pd(0)-catalyzed intramolecular Heck reaction: A general route for fused oxepine derivatives

A simple and facile approach for the synthesis of various structurally different tricyclic bent oxepine frameworks from a readily accessible precursor has been introduced. The synthesis of substituted oxepine derivative involved Pd(0)-catalyzed Heck reaction. This methodology enriches the literature for the large ring formation.     

Regioselective cross-coupling of allylindium reagents with activated benzylic bromides—a simple and efficient procedure for the synthesis of terminal alkenes

Allylindium reagents undergo facile and highly regioselective cross-coupling with benzylic and cinnamyl bromides in THF at room temperature without any catalyst producing terminal alkenes in high yields. The addition is highly regioselective and is found to provide γ-adducts in all reactions.     

Solvent-controlled highly selective bis- and monoallylation of active methylene compounds by allyl acetate with palladium(0) nanoparticle

Palladium(0) nanoparticle has been used as an efficient catalyst for the allylation of active methylene compounds. Very efficient bisallylation is achieved for a variety of active methylene compounds by allyl acetate and its derivatives in one stroke in THF solvent. The reaction in water provides monoallylated product selectively by allyl acetate only. The recovered Pd(0) nanoparticle is recycled. A probable mechanism is suggested.     

N‐bromosuccinimide reactions of some heterocycles in the presence or absence of water: An overview of ring versus side chain bromination for the synthesis of important brominated heterocyclic synthons

Reactions of various heterocycles 1–6 with N‐bromosuccinimide in the presence or absence of water have been studied for side chain versus ring bromination to afford some new and important heterocyclic synthons. Interestingly, the N‐bromosuccinimide reaction in the presence of perchloric acid, a new condition, affords exclusively the new dibromo aminopicoline 1f , which is not obtained by other presently studied methods.     

Iron-catalyzed annulation reaction of arylindium reagents and alkynes to produce substituted naphthalenes

We report here an iron–bisphosphine complex-catalyzed annulation reaction of an arylindium reagent and two alkyne molecules that affords a substituted naphthalene derivative in moderate to good yield. The reaction represents a new example of iron-catalyzed C–C bond forming reactions via C–H bond functionalization.