sulfonic acid functionalized sba-15 (sba-pr-so3h) with pore size 6 nm as an efficient heterogeneous nanoporous solid acid catalyst exhibited good catalytic activity in the biginelli-like reaction in the synthesis of spiroheterobicyclic rings with good yield and good recyclability. spiro-pyrimidinethiones/spiro-pyrimidinones-barbituric acid derivatives were synthesized in a simple and efficient ...

Synthesis of (4',5'-diaza-9'-fluorene)-spiro-5-hydantoin: The paper presents a method for synthesis of (4',5'-diaza-9'-fluorene)-spiro-5-hydantoin. The newly obtained compound was synthesized by a treatment of 4,5-diazafluoren-9-one with sodium cyanide, ammonium carbonate, ethanol and ammonium hydroxide at high pressure and high temperature. The structure of (4',5'-diaza-9'-fluorene)-spiro-5-hy...

carbon nanotubes (cnts) are specific structures with valuable characteristics. in general, the structure of each nanotube is defined by a unique chiral vector. in this paper, different structures of short single-walled cnts are simulated and their mechanical properties are determined using finite element method. for this aim, a simple algorithm is presented which is able to model the geometry o...

6'-(4-Chlorophenyl)-spiro[cyclohexane-1,2'-thieno[3,2-d][1,3] oxazin]-4'(1'H)-one (1) was synthesized and used as a starting material for the synthesis of a novel series of spiro compounds having biologically active sulfonamide 2a-e and 3'-(4-acetylphenyl)-6'- (4-chlorophenyl)-1'H-spiro[cyclohexane-1,2'-thieno[3,2-d] pyrimidine-4'(3'H)-one (3). Compound 2a was used as a key intermediate for the...

A facile construction of the spiro[indole-3,2'-pyrrolidine] skeleton, through diacetoxyiodobenzene (PIDA) mediated C-N bond-forming dearomatization of C3 sulfonamide linked indole derivatives, has been developed. A variety of spiro-indolepyrrolidines were obtained in moderate to excellent yields under mild conditions.

An exploration of the chemistry of the spiro-mamakone system, exemplified by the cytotoxic, fungal metabolite spiro-mamakone A, is presented. The first reported synthesis of the spiro-mamakone carbon skeleton was achieved, as well as the synthesis of a variety of closely related analogues of the natural product. Biological testing of the synthetic analogues generated a structure-activity profil...

The crystal structures of the new compounds spiro[cyclohexane-1,3’-indol]-2’(1’H)-one (1), (rel-1R,2S)-spiro[bicyclo[2.2.1] heptane-2,3’-indol]-2’(1’H)-one (2) and spiro[indole-3,2’-tricyclo[3.3.1.1]decan]-2(1H)-one (3) have been determined by low temperature single crystal X-ray diffraction. The effects of substitution on the hydrogen bonding pattern is compared between all three compounds.

One of the problems encountered in CE separations of basic compounds is the adsorption of analytes onto the negatively charged capillary wall which could lead to poor repeatability of migration time and peak area. Additionally, separation of enantiomers of chiral of basic drugs is commonly carried out in low pH buffer which contributes to strong ionic interaction of the cationic drug ions with ...

The hole transport material (HTM) of organic–inorganic perovskite solar cells (PVSCs) plays a very important role for achieving high power conversion efficiency and long-term stability. 2,2’,7,7’-tetrakis[N,N-di(4-methoxyphenyl)amino]-9-9’-spirobifluorene (spiro-OMeTAD) is the first solid-state HTM used in PVSCs has gained tremendous attention during last decade. Herein, concept spirolinkage sy...

A concise synthesis of spiro-cyclopropane compounds from indole derivatives and sulfur ylides has been developed via a dearomatization strategy. Moreover, the spiro-cyclopropane compounds could be conveniently transformed to rearomatized indole derivatives in the presence of acids.