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1.
Phase-transfer alkylation of the 2-oxocycloalkane-l-carbonitriles 1a and 1b with ethyl 4-bromo-3-methoxy-2-butenoate ( 2 ), followed by deprotection and base-catalyzed cyclization gave the annulated cyclopentenones 5a and 5b , respectively, in high overall yields (Scheme 1). Stereoselective catalytic hydrogenation of 5b followed by de-ethoxycarbonylation afforded 14-oxo-cis-bicyclo[10.3.0]pentadecane-l-carbonitrile ( 7 ). Treatment of 7 with LiN(i-Pr)2 in THF gave the known synthetic muscone precursor 8 (Scheme 2). The tricyclo[10.4.0.01,15]hexadecan-14-one ( 14 ) was prepared from 7 in 5 steps by a reaction sequence proceeding without affecting the chiral centres (Scheme 2). The structure of 14 was established by X-ray structure analysis (Figure). 相似文献
2.
Manol Ognyanov Petko Denev Desislava Teneva Yordan Georgiev Sabina Taneva Iskra Totseva Mariana Kamenova-Nacheva Yana Nikolova Svetlana Momchilova 《Molecules (Basel, Switzerland)》2022,27(6)
Gamma irradiation is efficiently applied to many foods, but nevertheless there is a distinct lack of information about the changes of macro- and micronutrients (e.g., carbohydrates, lipids, organic acids, and phenolics) in dried rose hip (RH) fruits. Therefore, in this study, for the first time, the effect of gamma irradiation (10 and 25 kGy) on RH constituents is investigated. Different analytical techniques (GC-FID, HPLC-UV, HPSEC-RID, IR-FT, and SEM) are employed to examine this effect. The irradiation treatment (10 kGy) increased the glucose content by 30% and released cellobiose from RH fruits, thus revealing cellulose destruction. The extractability of total uronic acids increased from 51% (control) to 70.5% (25 kGy-irradiated), resulting in a higher pectin yield (10.8% < 12.8% < 13.4%) and molecular heterogeneity. Moreover, de-esterification was not a major effect of the irradiation-induced degradation of pectin. The sample exposure to the highest dose did not change the content of total carotenoids, β-carotene, and (un)saturated fatty acids, but it affected the tocopherols levels. Gamma rays had a negligible effect on the phenolic constituents and did not affect ORAC and HORAC antioxidant activity. In conclusion, it can be compromised that the exposition of dried RH is safe and can be successfully applied to decontaminate fruits without affecting their nutritional value and biological activity. 相似文献
3.
4.
By one-step ring-enlargement reaction with isocyanates, 2-cyano- and 2-(ethoxycarbonyl)-substituted cycloalkanones are converted into macrocyclic imides. 相似文献
5.
Synthesis of Macrocyles by Ring Enlargement of 14-Membered Cyclic Imides In the presence of a base, cyclododecanone derivative 2 , activated in α-position by an allyloxycarbonyl group, underwent ring enlargement with isocyanates to give 14-membered imides (Schemes 1–3). Cleavage of the activating group gave new 14-membered imides which could be transformed by further ring-enlargement reactions into new macrocyclic compounds. 相似文献
6.
Germazane type sesquiterpenoids germazol (2), 7(11)-dihydrogermazol (3), 7(11)-dihydrogermazone (4), germazene-7(11) (17) and germazane (18) have been prepared from germazone (1). The presence and location of the cyclobutane ring in germazone (1) was confirmed by the acid-catalyzed cleavage of 2 to the cis-eudesmane derivatives 6,7 and 8. 相似文献
7.
Ohne Zusammenfassung
Spectrophotometric determination of carbonyl compoundsvia the 2,4-dinitrophenylhydrazones相似文献
8.
Vassil I. Ognyanov Marietta A. Haimova Nikola M. Mollov 《Monatshefte für Chemie / Chemical Monthly》1982,113(8-9):993-998
The title compounds5 were synthetized in two steps from the corresponding isoindolo[2,1–b]isoquinoline-5(7H)-ones3, obtained in high yields from 3-ethoxy-1H-isoindoles2 and homopthalic anhydrides1. TheStevens rearrangement of5 gave 2-methyl-2,3-dihydro-1H-isoindole-1-spiro-2-indanes6.
Synthese von 5,7,11 b,12-Tetrahydro-isoindolo[2,1-b]isochinolinium Methiodiden und ihre Stevens-Umlagerung
Zusammenfassung Die Titelverbindungen5 wurden in zwei Stufen aus den entsprechenden Isoindolo[2,1–b]isochinolin-5(7H)-onen (3) dargestellt, die ihrerseits in hohen Ausbeuten aus 3-Ethoxy-1H-isoindolen (2) und Homophthalsäureanhydriden erhältlich sind. DieStevens-Umlagerung von5 führte zu 2-Methyl-2,3-dihydro-1H-isoindol-1-spiro-2-indanen (6).相似文献
9.
Vassil I. Ognyanov Orlin S. Petrov Emil P. Tiholov Nikola M. Mollov 《Helvetica chimica acta》1989,72(2):353-360
Two gossypol analogues 2a and 2b were synthesized for biological evaluation as male contraceptive agents. The naphthol 8c was prepared by analogy with a known procedure starling from 3-isopropylcatechol ( 3 ). (t-Bu)2O2-Mediated phenolic coupling of 8c furnished the binaphthol 9c which, after pyrane ring closure, deprotection. and selective bisformylation with SnCl4/Cl2CHOCH3, gave the target compound 2a . The corresponding tetrahydroxy analogue 2b was prepared in a similar way. 相似文献
10.
By reaction with phenyl azide, 2-cyano- and 2-(ethoxycarbonyl)-substituted cyclododecanones are converted into 5-amino- and 5-hydroxy-1H-1,2,3-triazoles, respectively. The possible reaction mechanism is discussed. 相似文献