- Convergent and rapid assembly of benzonaphthopyranone cores of chartreusin, chrymutasins and hayumicins
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A new methodology for the rapid regiospecific synthesis of benzonaphthopyranones has been developed, on the basis of a tactical extension of the Hauser-Kraus annulation. The prowess of the methodology has been illustrated by a short synthesis of chartarin (22b) and a facile entry to the chrymutasin scaffold (26).
- Mal, Dipakranjan,Patra, Asit,Roy, Haren
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- Molecular Basis for the Final Oxidative Rearrangement Steps in Chartreusin Biosynthesis
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Oxidative rearrangements play key roles in introducing structural complexity and biological activities of natural products biosynthesized by type II polyketide synthases (PKSs). Chartreusin (1) is a potent antitumor polyketide that contains a unique rearranged pentacyclic aromatic bilactone aglycone derived from a type II PKS. Herein, we report an unprecedented dioxygenase, ChaP, that catalyzes the final α-pyrone ring formation in 1 biosynthesis using flavin-activated oxygen as an oxidant. The X-ray crystal structures of ChaP and two homologues, docking studies, and site-directed mutagenesis provided insights into the molecular basis of the oxidative rearrangement that involves two successive C-C bond cleavage steps followed by lactonization. ChaP is the first example of a dioxygenase that requires a flavin-activated oxygen as a substrate despite lacking flavin binding sites, and represents a new class in the vicinal oxygen chelate enzyme superfamily.
- Wang, Yi Shuang,Zhang, Bo,Zhu, Jiapeng,Yang, Cheng Long,Guo, Yu,Liu, Cheng Li,Liu, Fang,Huang, Huiqin,Zhao, Suwen,Liang, Yong,Jiao, Rui Hua,Tan, Ren Xiang,Ge, Hui Ming
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supporting information
p. 10909 - 10914
(2018/09/10)
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- Rapid Access to Orthogonally Functionalized Naphthalenes: Application to the Total Synthesis of the Anticancer Agent Chartarin
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We report the synthesis of orthogonally functionalized naphthalenes from simple, commercially available indanones in four steps. The developed method proceeds through a two-step process that features a thermally induced fragmentation of a cyclopropane indanone with simultaneous 1,2-chloride shift. Migration of the chloride substituent occurs in a regioselective manner to preferentially afford the para-chloronaphthol substitution pattern. The obtained naphthols are versatile building blocks that can be selectively modified and used for the efficient construction of biologically active molecules. This has enabled the total synthesis of the potent anticancer natural product chartarin through a highly convergent retrosynthetic bond disconnection.
- Unzner, Teresa A.,Grossmann, Adriana S.,Magauer, Thomas
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supporting information
p. 9763 - 9767
(2016/08/10)
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- NOVEL CHARTREUSIN ANALOGUES
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The present invention relates to novel Chartreusin analogues of formula (I), pharmaceutical compositions comprising the same and to their use for the treatment of cancer and other diseases.
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Page/Page column 12; 28; 30; 31
(2014/02/16)
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- Synthetic remodeling of the chartreusin pathway to tune antiproliferative and antibacterial activities
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Natural products of the benzonaphthopyranone class, such as chartreusin, elsamicin A, gilvocarcin, and polycarcin, represent potent leads for urgently needed anticancer therapeutics and antibiotics. Since synthetic protocols for altering their architectur
- Ueberschaar, Nico,Xu, Zhongli,Scherlach, Kirstin,Metsae-Ketelae, Mikko,Bretschneider, Tom,Dahse, Hans-Martin,Goerls, Helmar,Hertweck, Christian
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supporting information
p. 17408 - 17416
(2014/01/06)
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- Tandem annulation strategy for the convergent synthesis of benzonaphthopyranones: total synthesis of chartarin and O-methylhayumicinone
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A Hauser-initiated tandem annulation has been developed for the rapid regiospecific synthesis of benzonaphthopyranones via formation of two rings in one-pot operation. This strategy has been generalized with benzonaphthopyranones 26, 29, 32, and 35. It has also been employed in a short synthesis of chartarin (3) and O-methylhayumicinone (67).
- Ray, Sutapa,Patra, Asit,Mal, Dipakranjan
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p. 3253 - 3267
(2008/09/19)
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- Elsamicins A and B, New Antitumor Antibiotics Related to Chartreusin. 2. Structures of Elsamicins A and B
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The structures of new antitumor antibiotics elsamicins A (1a) and B (1b), produced by an unidentified actinomycete strain J907-21, have been established by a combination of chemical degradation, spectral analysis, and X-ray diffraction.They are structurally similar to chartreusin containing chartarin as an aglycon, but differ to each other in sugar moieties.Elsamicin A possesses two novel sugars, 2-amino-2,6-dideoxy-3-O-methyl-D-galactose and 6-deoxy-3-C-methyl-D-galactose.The presence of the amino sugar makes elsamicin A remarkably water-soluble and more bioactive than chartreusin.Elsamicin B differs from elsamicin A in that it lacks the amino sugar moiety.
- Sugawara, Koko,Tsunakawa, Mitsuaki,Konishi, Masataka,Kawaguchi, Hiroshi,Krishnan, Bala,et al.
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p. 996 - 1001
(2007/10/02)
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- Synthesis and antitumor activity of analogues of the antitumor antibiotic chartreusin
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First isolated in 1953 from a fermentation broth, chartreusin (1) has received interest as a result of substantial antitumor activities recently demonstrated in several murine test systems. Poor water solubility frustrated formulation attempts, and rapid
- Takai,Uehara,Beisler
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p. 549 - 553
(2007/10/02)
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- Synthesis of Chartreusin Aglycone
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A short regiospecific synthesis of chartreusin aglycone (2) is described.Diels-Alder addition of 4 and 5 under oxidizing conditions affords benzanthracenedione 6.Reductive methylation of 6 gives 7 (90percent), which is oxidatively cleaved to diacid 8 (54p
- Kelly, T. Ross,Magee, Joseph A.,Weibel, Franz R.
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p. 798 - 799
(2007/10/02)
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