- Synthesis and characterization of photoaffinity labelling reagents towards the Hsp90 C-terminal domain
-
Glucosyl-novobiocin-based diazirine photoaffinity labelling reagents (PALs) were designed and synthesized to probe the Hsp90 C-terminal domain unknown binding pocket and the structure-activity relationship. Five PALs were successfully synthesized from novobiocin in six consecutive steps employing phase transfer catalytic glycosylation. Reactions were monitored and guided by analytical LC/MS which led to different strategies of adding either a PAL precursor or a sugar moiety first. The structures and bonding linkages of these compounds were characterised by various 2D-NMR spectroscopy and MS techniques. Synthetic techniques provide powerful probes for unknown protein binding pockets.
- Simon, Binto,Huang, Xuexia,Ju, Huangxian,Sun, Guoxuan,Yang, Min
-
-
Read Online
- NOVOBIOCIN ANALOGUES AND TREATMENT OF POLYCYSTIC KIDNEY DISEASE
-
Novobiocin analogues are useful in methods of treating, inhibiting, and/or preventing cyst formation in autosomal dominant polycystic kidney disease (ADPKD) in a subject. The disclosure provides methods of treating ADPKD comprising administering a therapeutically effective amount of a coumarin-3-carboxamide novobiocin analogue. Accordingly, the method can include administering a novobiocin analogue in a therapeutically effective amount for reducing levels of mTOR pathway phosphoproteins P-mTOR, P-Akt and P-S6K, or combinations thereof. Further, the method can include administering a novobiocin analogue in a therapeutically effective amount for reducing levels of Hsp-90 client proteins CFTR, ErbB2, c-Raf and Cdk4, or combinations thereof.
- -
-
-
- Novobiocin: Redesigning a DNA gyrase inhibitor for selective inhibition of Hsp90
-
Novobiocin is a member of the coumermycin family of antibiotics and is a well-established inhibitor of DNA gyrase. Recent studies have shown that novobiocin binds to a previously unrecognized ATP-binding site at the C-terminus of Hsp90 and induces degradation of Hsp90-dependent client proteins at ~700 μM. In an effort to develop more efficacious inhibitors of the C-terminal binding site, a library of novobiocin analogues was prepared and initial structure-activity relationships revealed. These data suggested that the 4-hydroxy moiety of the coumarin ring and the 3′-carbamate of the noviose appendage were detrimental to Hsp90 inhibitory activity. In an effort to confirm these findings, 4-deshydroxy novobiocin (DHN1) and 3′-descarbamoyl-4- deshydroxynovobiocin (DHN2) were prepared and evaluated against Hsp90. Both compounds were significantly more potent than the natural product, and DHN2 proved to be more active than DHN1. In an effort to determine whether these moieties are important for DNA gyrase inhibition, these compounds were tested for their ability to inhibit DNA gyrase and found to exhibit significant reduction in gyrase activity. Thus, we have established the first set of compounds that clearly differentiate between the C-terminus of Hsp90 and DNA gyrase, converted a well-established gyrase inhibitor into a selective Hsp90 inhibitor, and confirmed essential structure-activity relationships for the coumermycin family of antibiotics.
- Burlison, Joseph A.,Neckers, Len,Smith, Andrew B.,Maxwell, Anthony,Blagg, Brian S. J.
-
p. 15529 - 15536
(2007/10/03)
-