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101.
Physics of the Solid State - The influence of deposition parameters, such as: the magnetron power in the range 690–1400 W, the silicon substrate temperature 23–170°C, the N2 gas...  相似文献   
102.
1-Anilinocycloalkanecarbonitriles 1a–c were prepared and reacted with active methylene reagents to give compounds 5a–c through 10a–c and reacted with different other reagents such as benzaldehyde, ethyl aminoacetate, ethyl mercaptoacetate, or hydrazine carbothioamide, which afforded the desired spiro heterocycles compounds 11a–c through 14a–c.  相似文献   
103.
A marine fungal isolate, identified as Drechslera sp., was mass cultivated and found to produce a new naturally occurring seco-sativene type sesquiterpene helminthosporic acid (1) and three known sesquiterpenes, helminthosporol (2), drechslerine A (3) and (+) secolongifolene-diol (4). The structures of all compounds were determined by interpretation of their spectroscopic data 1D (1H and 13C), 2D (COSY, DQF, NOE, HSQC and HMBC) NMR, MS, UV and IR analyses. All compounds have been tested toward antioxidants, antimicrobial and antifouling effects.  相似文献   
104.
Abstract

N-Phenylmorpholine (1) reacted with chlorosulfonic acid to give the p-sulfonyl chloride (2), which was characterized as the sulfonamides (35). Benzothiazole (6) was converted into the sulfonyl chloride (7) by sequential treatment with hot chlorosulfonic acid and thionyl chloride. Reaction of (7) with amines afforded the derivatives (810); NMR spectral analysis of the dimethylamide (8) indicated that it was a mixture of the 4- and 7-isomers. Chlorosulfonation of 2-methylbenzothiazole (11) was achieved by heating with chlorosulfonic acid with or without thionyl chloride. The chloride (12) was converted into amides (1319). Study of the NMR spectra indicated that mixtures of the 5- and 6-isomers were formed. 2,4,5-Triphenyloxazole (20) reacted with chlorosulfonic acid to give either the mono-(21), bis (23) or bis-tris sulfonylchlorides (23, 34); these were converted into 14 sulfonamides. 2-(p-Nitrophenyl)-4,5-diphenyloxazole (41) reacted with hot chlorosulfonic acid to give the bis-sulfonyl chloride (42), characterized as the dimethylsulfonamide (43). Attempts to form the pure monosulfonyl chloride and to mono nitrate 2,4,5-triphenyloxazole (20) were unsuccessful.  相似文献   
105.
A novel methodology has been devised for the chemoselective reduction of enones involving the use of n Bu3SnH and azobisisobutyronitrile. The 1,4-reduction of variously substituted α,β-unsaturated cyclic and acyclic enones has been successfully carried out under free radical reaction conditions. The reaction has been determined to proceed via single-electron transfer.

[Supplementary materials are available for this article. Go to the publisher's online edition of Synthetic Communications® for the following free supplemental resource(s): Full experimental and spectral details.]  相似文献   

106.
Two further lasiodiplodins, (3R,4R)-4-hydroxy-de-O-methyl-lasiodiplodin and (E)-9-etheno-de-O-methyl-lasiodiplodin, together with three known lasiodiplodins from a cytotoxic extract obtained from a culture of Lasiodiplodia theobromae, an endophyte from the root tissues of Mapania kurzii (Cyperaceae) from the Malaysian rain forest, were characterized on microgram scale.  相似文献   
107.
The investigation of carbonic anhydrase and paraoxonase enzyme inhibition properties of water-soluble zinc and gallium phthalocyanine complexes ( 1 and 2 ) are reported for the first time. The binding of p-sulfonylphenoxy moieties to the phthalocyanine structure favors excellent solubilities in water, as well as providing an inhibition effect on carbonic anhydrase (CA) I and II isoenzymes and paraoxonase (PON1) enzyme. According to biological activity results, both complexes inhibited hCA I, hCA II, and PON1. Whereas 1 and 2 showed moderate hCA I and hCA II (off-target cytosolic isoforms) inhibitory activity (Ki values of 26.09 µM and 43.11 µM for hCA I and 30.95 µM and 33.19 µM for hCA II, respectively), they exhibited strong PON1 (associated with high-density lipoprotein [HDL]) inhibitory activity (Ki values of 0.37 µM and 0.27 µM, respectively). The inhibition kinetics were analyzed by Lineweaver–Burk double reciprocal plots. It revealed that 1 and 2 were noncompetitive inhibitors against PON1, hCA I, and hCA II. These complexes can be more advantageous than other synthetic CA and PON inhibitors due to their water solubility. Docking studies were carried out to examine the interactions between hCA I, hCA II, and PON1 inhibitors and metal complexes at a molecular level and to predict binding energies.  相似文献   
108.
Nanogram amounts of cyanide were indirectly determined by molecular emission cavity analysis. The method is based on the reaction of cyanide with sulphite-formaldehyde addition compound and the measurement of the S2 emission produced either from the sulphite released or from the addition compound. The relative standard deviations are 2.13% and 1.66% and the recoveries are 99% and 100% using the released sulphite peak and the addition compound peak, respectively. Potential interfering anions were investigated.  相似文献   
109.
110.
Hybrid copper molybdates containing the long‐spanning bis(4‐pyridylmethyl) piperazine (bpmp) ligand were prepared via hydrothermal synthesis and structurally characterized by single‐crystal X‐ray diffraction. The reduced copper phase and major product [Cu4(MoO4)2(bpmp)4]n ( 1 ) shows 1D ribbon motifs with embedded {CuI2O2} dimeric units, built from the bpmp pillaring of [Cu4(MoO4)2] linear clusters. The oxidized copper phase and minor product {[Cu2(MoO4)2(bpmp)4] · 24H2O}n ( 2 ) displays [Cu(bpmp)2]n2n+ mutually inclined interpenetrated cationic layers cross‐pillared by molybdate tetrahedra into an unprecedented 6‐connected self‐penetrated network with 485265 topology.  相似文献   
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