Deep eutectic solvent an efficient reaction medium for the synthesis of chromeno pyrazolo and indazolo phthalazine derivatives

The volatile, harmful and hazardous solvents have impact on human health, all organisms and environment. To reduce the use of hazardous volatile solvents, there is need to develop the alternative green reaction medium for organic transformations and is the main goal of green chemistry. The green solvent should be nonvolatile, nontoxic, biodegradable and biorenewable. Considering these parameters, herein, we have reported an efficient and environmentally benign green synthesis of chromeno pyrazolo and indazolo phthalazine derivatives in deep eutectic solvent. The present protocol contains excellent yield of the product, short reaction time, operation simplicity, reusability of solvent and no need of further purification.     

Polyelectrolyte Configuration of Low Molecular Weight Sodium Amylose Xanthate in Aqueous and Salt Solutions

The polyelectrolyte chain configuration of low molecular weight sodium amylose xanthate (NaAX) in aqueous and salt solutions has been studied by viscometry and light scattering. The viscometric results in aqueous solution have been found to be in accordance with the Fuoss's modified equation. The intrinsic viscosities of NaAX in salt solutions from 0.00125 to 0.25 M NaCl have been determined and the expansion factor a at each ionic strength has been determined. The dependence of a on ionic strength has been studied according to the theories of Hermans and Overbeek, Flory, etc. But though qualitative agreement between experimental and theoretical results has been found, quantitative agreement was far from expectations. The frictional coefficient per monomer unit | has been calculated from the relationship of Kirkwood and Riseman. The NaAX macromolecule has been found to have the polydispersed random coil chain configuration in 0.25 M NaCl. Some macromolecular configurational parameters such as effective bond length b, Kuhn-Kuhn equivalent chain length A_m, and steric factor α has been determined.     

Microporous carbon aerogel prepared through ambient pressure drying route as anode material for lithium ion cells

Carbon aerogel synthesized through a cost‐effective and easy method was evaluated and found to be a promising anode material for lithium ion cells. Carbon aerogel was prepared by carbonizing resorcinol–formaldehyde (RF) aerogel under inert atmosphere. Resorcinol–formaldehyde aerogel in turn was prepared through sol gel polymerization of resorcinol with formaldehyde using sodium carbonate as catalyst adopting ambient pressure drying route. The structure and the morphology of the prepared carbon aerogel are investigated using X‐ray diffraction (XRD), scanning electron microscopy (SEM) and transmission electron microscopy (TEM) and surface area determined using N₂–Brunauer–Emmett–Teller (BET) method. The TEM images reveal microporous morphology of the carbon aerogel particles. The evaluation of carbon aerogel as an anode material revealed promising specific capacity synergized with outstanding cyclability. The first cycle specific capacity was 288 mAh/g with an efficiency of 63% at C/10 rate. The material retained a capacity of 96.9% of the initial capacity with about 100% efficiency after 100 cycles, showing the excellent cyclability of the material. Copyright © 2017 John Wiley & Sons, Ltd.     

Synthesis and evaluation of a fluorescent ritterazine-cephalostatin hybrid

The cephalostatin and ritterazine natural products comprise a potent family of bis-steroidal pyrazines that display potent single-digit nanomolar inhibition of tumor cell growth. An active fluorescent ritterazine-cephalostatin hybrid probe was developed using detailed SAR data derived through total synthetic efforts. A combination of time course and confocal imaging studies indicate that this natural product family is rapidly taken up in tumor cells and localizes subcellularly within ER and surrounding the nuclear-ER interface.     

Crystal and Molecular Structure Studies of 1′-Benzyl-8-(4-fluorobenzyl)-8-azaspiro[bicyclo-[3.2.1]octane-3,4′-imidazolodine]-2′,5′-dione

Abstract  

The title compound, C₂₃H₂₃FN₃O₂ has been synthesized and the structure was investigated by X-ray diffraction studies. The compound crystallizes in the triclinic crystal class in the space group P[`1]P\overline{1} with cell parameters a = 9.345(2) ?, b = 10.940(3) ?, c = 11.986(4) ?, α = 72.349(6)°, β = 68.106(18)°, γ = 66.867(5)°, Z = 2 and V = 1027.8(5) ?³. The hydantoin ring adopts a planar conformation and is affected by the π conjugation. The pyrrolidine and piperidine rings in the bicyclo octane moiety adopt envelope and chair conformations respectively. The structure exhibits both inter and intramolecular hydrogen bonds of the type N–H···O, C–H···O and C–H···N. One of the oxygen atoms attached to the hydantoin ring simultaneously accepts two hydrogen bonds to form a three centered hydrogen bonding pattern.     

A concise synthesis of the bioactive meroterpenoid natural product (±)-liphagal, a potent PI3K inhibitor

A short, diversity-oriented synthesis that follows a biomimetic route to the marine natural product liphagal, from a commercially available building block, is delineated.     

A highly efficient precatalytic system (XPhos-PdG2) for the Suzuki–Miyaura cross-coupling of 7-chloro-1H-pyrrolo[2,3-c]pyridine employing low catalyst loading

Molecular Diversity - An expedient catalytic method for the synthesis of diverse 7-(hetero) aryl-1H-pyrrolo[2,3-c]pyridine analogues via microwave-assisted Suzuki–Miyaura cross-coupling...