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Topopyrone B

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Topopyrone B
Category Enzyme inhibitors
Catalog number BBF-02701
CAS
Molecular Weight 372.71
Molecular Formula C18H9ClO7

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Fermentation Lab

4 R&D and scale-up labs

2 Preparative purification labs

Fermentation Plant

Semi pilot, pilot and industrial plant 4 Manufacturing sites 7 Production lines at pilot scale 100+ Reactors of 30-4000 L; 170+ reactors of 20 KL-30 KL; 24+ reactors of >100 KL 2 Hydrogenation reactors (200 L, 4Mpa and 1000L, 4Mpa)

Product Description

It is produced by the strain of Phoma sp. BAUA 2861 and Penicillum sp. BAUA 4206. Topopyrone B selectively inhibits topoisomerase I with the IC50 of 0.15 ng/mL. It also has anti-Gram-positive bacteria activity and it has a strong inhibitory effect on herpes virus, especially varicella zoster virus (VZV).

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IUPAC Name 8-chloro-5,7,9-trihydroxy-2-methylnaphtho[3,2-g]chromene-4,6,11-trione
Canonical SMILES CC1=CC(=O)C2=C(O1)C=C3C(=C2O)C(=O)C4=C(C(=C(C=C4C3=O)O)Cl)O
InChI InChI=1S/C18H9ClO7/c1-5-2-8(20)13-10(26-5)4-7-11(17(13)24)16(23)12-6(15(7)22)3-9(21)14(19)18(12)25/h2-4,21,24-25H,1H3
InChI Key XQMOGUIQWMFPBF-UHFFFAOYSA-N
Appearance White Powder
Antibiotic Activity Spectrum Gram-positive bacteria; viruses
Melting Point >280°C
1. Novel human topoisomerase I inhibitors, topopyrones A, B, C and D. II. Structure elucidation
D Ishiyama, Y Kanai, H Senda, W Iwatani, W Iwatani, H Konno, S Kanazawa J Antibiot (Tokyo). 2000 Sep;53(9):873-8. doi: 10.7164/antibiotics.53.873.
The structures of novel topoisomerase I inhibitors, topopyrones A, B, C and D were elucidated by spectral analysis of the chemical derivatives. These compounds are an anthraquinone type containing a fused 1,4-pyrone moiety. Topopyrones A and B contain a chlorine atom, however C and D do not. It was suggested that topopyrones B and D are converted from topopyrones A and C, respectively by Wessely-Moser type rearrangement.
2. Total synthesis of topopyrones B and D
Jason Samuel Tan, Marco A Ciufolini Org Lett. 2006 Oct 12;8(21):4771-4. doi: 10.1021/ol0617291.
[reaction: see text] We describe a straightforward synthesis of topopyrones B and D, which are potent and selective inhibitors of topoisomerase I. The chemistry should be suitable for additional structure-activity relationship (SAR) work.
3. Identification and Heterologous Expression of the Topopyrone Nonaketide Synthase Gene from Phoma sp
Nobuyuki Kashiwa, Yutaka Ebizuka, Isao Fujii Chem Pharm Bull (Tokyo). 2016;64(7):947-51. doi: 10.1248/cpb.c16-00172.
Non-reducing iterative type I polyketide synthase genes, pnk1 and pnk2, were cloned from the fungus Phoma sp. BAUA2861, which produces the topoisomerase I inhibitors, topopyrones A to D. Heterologous expression of these polyketide synthase genes under the α-amylase promoter in Aspergillus oryzae was carried out to identify their functions. The pnk2 transformant produced topopyrones C, D, and haematommone. Therefore, the pnk2 gene was found to encode for the topopyrone nonaketide synthase.

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