622-33-3Relevant articles and documents
A Pictet-Spengler ligation for protein chemical modification
Agarwal, Paresh,Van Der Weijden, Joep,Sletten, Ellen M.,Rabuka, David,Bertozzi, Carolyn R.
, p. 46 - 51 (2013)
Aldehyde- and ketone-functionalized proteins are appealing substrates for the development of chemically modified biotherapeutics and protein-based materials. Their reactive carbonyl groups are typically conjugated with α-effect nucleophiles, such as substituted hydrazines and alkoxyamines, to generate hydrazones and oximes, respectively. However, the resulting C=N linkages are susceptible to hydrolysis under physiologically relevant conditions, which limits the utility of such conjugates in biological systems. Here we introduce a Pictet-Spengler ligation that is based on the classic Pictet- Spengler reaction of aldehydes and tryptamine nucleophiles. The ligation exploits the bioorthogonal reaction of aldehydes and alkoxyamines to form an intermediate oxyiminium ion; this intermediate undergoes intramolecular C-C bond formation with an indole nucleophile to form an oxacarboline product that is hydrolytically stable. We used the reaction for site-specific chemical modification of glyoxyl- and formylglycine-functionalized proteins, including an aldehyde-tagged variant of the therapeutic monoclonal antibody Herceptin. In conjunction with techniques for site-specific introduction of aldehydes into proteins, the Pictet-Spengler ligation offers a means to generate stable bioconjugates for medical and materials applications.
Vinylogous Aza-Michael Addition of Urea Derivatives with p-Quinone Methides Followed by Oxidative Dearomative Cyclization: Approach to Spiroimidazolidinone Derivatives
Kaur, Navpreet,Singh, Priyanka,Banerjee, Prabal
supporting information, p. 2813 - 2824 (2021/04/21)
Herein, we report an efficient protocol for the synthesis of spiro-imidazolidinone-cyclohexadienones from p-quinone methides (p-QMs) and dialkyloxy ureas under mild conditions. The strategy follows a two-step process involving an initial vinylogous conjugate addition of urea derivatives to p-QMs, followed by oxidative dearomative cyclization of open-chain product to the projected spiro-imidazolidinones. This protocol exhibits good functional group tolerance and provides a straightforward method to access spiro-imidazolidinone-cyclohexadienones. In follow-up chemistry, we have shown the debenzylation of spiroimidazolidinones to give N-hydroxycyclic ureas. (Figure presented.).
Novel fluorinated 7-hydroxycoumarin derivatives containing an oxime ether moiety: Design, synthesis, crystal structure and biological evaluation
Dai, Peng,Jiao, Jian,Wang, Qing-Qing,Zhang, Shu-Guang,Zhang, Wei-Hua
, (2021/06/28)
A series of fluorinated 7-hydroxycoumarin derivatives containing an oxime ether moiety have been designed, synthesized and evaluated for their antifungal activity. All the target compounds were determined by1H-NMR,13C-NMR, FTIR and HR-MS spectra. The single-crystal structures of compounds 4e, 4h, 5h and 6c were further confirmed using X-ray diffraction. The antifungal activities against Botrytis cinerea (B. cinerea), Alternaria solani (A. solani), Gibberella zeae (G. zeae), Rhizoctorzia solani (R. solani), Colletotrichum orbiculare (C. orbiculare) and Alternaria alternata (A. alternata) were evaluated in vitro. The preliminary bioassays showed that some of the designed compounds displayed the promising antifungal activities against the above tested fungi. Strikingly, the target compounds 5f and 6h exhibited outstanding antifungal activity against B. cinerea at 100 μg/mL, with the corresponding inhibition rates reached 90.1 and 85.0%, which were better than the positive control Osthole (83.6%) and Azoxystrobin (46.5%). The compound 5f was identified as the promising fungicide candidate against B. cinerea with the EC50 values of 5.75 μg/mL, which was obviously better than Osthole (33.20 μg/mL) and Azoxystrobin (64.95 μg/mL). Meanwhile, the compound 5f showed remarkable antifungal activities against R. solani with the EC50 values of 28.96 μg/mL, which was better than Osthole (67.18 μg/mL) and equivalent to Azoxystrobin (21.34 μg/mL). The results provide a significant foundation for the search of novel fluorinated 7-hydroxycoumarin derivatives with good antifungal activity.
