21622-08-2Relevant articles and documents
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Ayerst,Schofield
, p. 4097,4101 (1958)
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(E)-3-(2,2-dibromospiro[2.4]heptan-1-yl)-propenenitrile
Banwell, Martin G.,Hockless, David C. R.,Wu, Angela W.
, p. 504 - 506 (1997)
The X-ray crystal structure of the title compound, C10H11Br2N, reveals that the three- and five-membered rings are fused to one another in a spiro fashion and that there is an E arrangement of substituents about the carbon-carbon double bond.
Synthesis of novel shikonin derivatives and pharmacological effects of cyclopropylacetylshikonin on melanoma cells
Durchschein, Christin,Bauer, Rudolf,Kretschmer, Nadine,Hufner, Antje,Rinner, Beate,Stallinger, Alexander,Deutsch, Alexander,Lohberger, Birgit
supporting information, (2018/11/23)
Despite much research in the last centuries, treatment of malignant melanoma is still challenging because of its mostly unnoticeable metastatic spreading and aggressive growth rate. Therefore, the discovery of novel drug leads is an important goal. In a previous study, we have isolated several shikonin derivatives from the roots of Onosma paniculata Bureau & Franchet (Boraginaceae) which evolved as promising anticancer candidates. β,β-Dimethylacrylshikonin (1) was the most cytotoxic derivative and exhibited strong tumor growth inhibitory activity, in particular, towards melanoma cells. In this study, we synthesized eighteen novel shikonin derivatives in order to obtain compounds which exhibit a higher cytotoxicity than 1. We investigated their cytotoxic potential against various melanoma cell lines and juvenile skin fibroblasts. The most active compound was (R)-1-(1,4-dihydro-5,8-dihydroxy-1,4-dioxonaphthalen-2-yl)-4-methylpent-3-enyl cyclopropylacetate (cyclopropylacetylshikonin) (6). It revealed significant stronger tumor growth inhibitory activity towards two melanoma cell lines derived from metastatic lesions (WM164 and MUG-Mel2). Further investigations have shown that 6 induced apoptosis caspase-dependently, increased the protein levels of cleaved PARP, and led to double-stranded DNA breaks as shown by phosphorylation of H2AX. Cell membrane damage and cell cycle arrest were not observed.
Reaction of N-acetylimidazole with enamines
Cook, Gilbert,Waddle, Julie L.
, p. 6923 - 6925 (2007/10/03)
N-Acetylimidazole is a commonly used acylating reagent. When it is allowed to react with several typical enamines, amides are produced rather than the expected acylated enamines.
