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1.
Reaction of dienamine 4a with substituted phenacyl bromides gave steroidal[3,4-b] furans 5a–g. The same principle reaction was utilized for the total synthesis of (±) 2 - (p - chlorophenyl) - 3 - oxa - A - nor - estra - 1,5(10), 9(11) - triene - 17 - acetate 12a. Treatment of 4a, b with benzenediazonium salts, in DMF, followed by a Fischer-indole cyclization yielded steroidal[6, 7-b] indoles 8a–k. Dienamine 4b could be annelated to benz[4, 5, 6] steroids 9a and 9b by reaction with methyl vinyl ketone and crotonaldehyde, respectively.  相似文献   
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A series of heterocyclic analogs of diarylethylene and triarylethylene were synthesized as potential anti-implantation agents. Tested in rats as oral, post-coital antifertilily agents, a few of our compounds showed some activity.  相似文献   
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This study investigated the organic and inorganic constituents of healthy leaves and Candidatus Liberibacter asiaticus (CLas)-inoculated leaves of citrus plants. The bacteria CLas are one of the causal agents of citrus greening (or Huanglongbing) and its effect on citrus leaves was investigated using laser-induced breakdown spectroscopy (LIBS) combined with chemometrics. The information obtained from the LIBS spectra profiles with chemometrics analysis was promising for the construction of predictive models to identify healthy and infected plants. The major, macro- and microconstituents were relevant for differentiation of the sample conditions. The models were then applied to different inoculation times (from 1 to 8 months). The models were effective in the classification of 82-97% of the diseased samples with a 95% significance level. The novelty of this method was in the fingerprinting of healthy and diseased plants based on their organic and inorganic contents.  相似文献   
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A safer, greener, and more effective reaction methodology for the synthesis of dihydroquinazolinones (DHQs) has been developed. The deep eutectic solvent (DES) ZnCl2/urea employed in this study efficiently accelerated the cyclization of 2-aminobenzamide with different aldehydes (aromatic and heteroaromatic) to afford the target scaffolds without the generation of any oxidized product. This method has exhibited remarkable advantages such as quick reaction time, mild reaction conditions, high yield (82%–98%), operational simplicity, and selectivity. The approach was observed to be tolerant to electron-donating and electron-withdrawing functional groups. Green metric parameters (AEf, OE, AE, RME, CE, etc.) determined further aided this greener chemical approach.  相似文献   
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New copper(II) acetate complexes with the saturated diheterocyclic bases (L-L): piperazine, 1-methylpiperazine, and 1,4-dimethylpiperazine and their monohydrochlorides, have been prepared and characterised by physico-chemical and spectroscopic methods. They are magnetically dilute and antiferromagnetic, with stoichiometries of the type Cu(OAc)2(B)n(B=L-L or L-LHCl and n=2, 1 or 0.5).  相似文献   
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Let B(EF) be the Banach Space of all continuous linear operators from a Banach Space E into a Banach space F. Let UX and UY be balanced open subsets of Banach spaces X and Y, respectively. Let V and W be two Nachbin families of continuous weights on UX and UY, respectively. Let HV(UXE) (or HV0(UXE)) and HW(UYF) (or HW0(UYF)) be the weighted spaces of vector-valued holomorphic functions. In this paper, we investigate the holomorphic mappings ? : UY → UX and ψ : UY → B(EF) which generate weighted composition operators between these weighted spaces.  相似文献   
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