85432-87-7Relevant academic research and scientific papers
Total Synthesis of Clavilactones
Takao, Ken-Ichi,Mori, Kento,Kasuga, Kenya,Nanamiya, Ryuki,Namba, Ayumi,Fukushima, Yuuki,Nemoto, Ryuichi,Mogi, Takuma,Yasui, Hiroyuki,Ogura, Akihiro,Yoshida, Keisuke,Tadano, Kin-Ichi
, p. 7060 - 7075 (2018/07/15)
Clavilactones A, B, and D are epidermal growth factor receptor tyrosine kinase inhibitors that were isolated from cultures of the fungus Clitocybe clavipes. Here, we report full details of the total synthesis of these clavilactones. A key feature of our s
Total synthesis of the aglycone of IB-00208
Knueppel, Daniel,Yang, Jingyue,Cheng, Bo,Mans, Douglas,Martin, Stephen F.
, p. 5741 - 5757 (2015/08/03)
Abstract A total synthesis of the aglycone of IB-00208 was accomplished in 22 steps using a newly developed approach towards polycyclic 1,4-dioxygenated xanthones from benzocyclobutenones. The generality of this entry to xanthones was initially established on several model systems before it was successfully applied to the construction of the hexacyclic core of the natural product. A new and potentially general approach towards angularly fused benzocyclobutenones using ring-closing metathesis (RCM) was also developed.
Synthesis of a landomycinone skeleton via Masamune-Bergmann cyclization
Yamaguchi, Sho,Tanaka, Hiroshi,Yamada, Ryo,Kawauchi, Susumu,Takahashi, Takashi
, p. 32241 - 32248 (2014/08/18)
In this report, a synthetic study of landomycinone via Masamune-Bergmann cyclization is described. A 10-membered 1,2-dialkynylbenzene derivative was designated as a key intermediate in the formation of an angular tetracyclic core via Masamune-Bergmann cyclization. Cyclization was expected to proceed under mild heating conditions based on a DFT transition state analysis of the 10-membered enediyne. The enediyne was successfully prepared by intramolecular NHK cyclization in good yield and underwent Masamune-Bergman cyclization at 70 °C for 2 h. However, an undesired β-elimination of the secondary alcohol was involved in the cyclization. In addition, iodination at the 12 position did not occur due to the steric hindrance of two methyl groups. This methodology should be widely applicable to the synthesis of various types of highly oxy-functionalized anthraquinone derivatives as well as landomycinone, and should be a useful way to clarify structure-activity relationships. the Partner Organisations 2014.
Total synthesis of (+)-clavilactone A and (-)-clavilactone B by ring-opening/ring-closing metathesis
Takao, Ken-Ichi,Nanamiya, Ryuki,Fukushima, Yuuki,Namba, Ayumi,Yoshida, Keisuke,Tadano, Kin-Ichi
supporting information, p. 5582 - 5585 (2013/11/19)
The enantioselective total synthesis of natural enantiomers of clavilactones A and B has been achieved. A key feature of the synthesis is the use of a ring-opening/ring-closing metathesis, which allows the one-pot transformation of a strained cyclobutenecarboxylate into a γ-butenolide.
Efficient method for synthesis of angucyclinone antibiotics via gold-catalyzed intramolecular [4 + 2] benzannulation: Enantioselective total synthesis of (+)-ochromycinone and (+)-rubiginone B2
Sato, Kenichiro,Asao, Naoki,Yamamoto, Yoshinori
, p. 8977 - 8981 (2007/10/03)
An efficient synthetic approach to angucyclinone antibiotics, (+)-ochromycinone and (+)-rubiginone B2, is reported. The key step involves the facile formation of 2,3-dihydrophenantren-4(1H)-one skeleton, an important framework of angucyclinone
Total synthesis of the quinone epoxide dimer (+)-torreyanic acid: Application of a biomimetic oxidation/electrocyclization/Diels-Alder dimerization cascade
Li, Chaomin,Johnson, Richard P.,Porco Jr., John A.
, p. 5095 - 5106 (2007/10/03)
An asymmetric synthesis of the quinone epoxide dimer (+)-torreyanic acid (48) has been accomplished employing [4 + 2] dimerization of diastereomeric 2H-pyran monomers. Synthesis of the related monomeric natural product (+)-ambuic acid (2) has also been achieved which establishes the biosynthetic relationship between these two natural products. A tartrate-mediated nucleophilic epoxidation involving hydroxyl group direction facilitated the asymmetric synthesis of a key chiral quinone monoepoxide intermediate. Thermolysis experiments have also been conducted on a model dimer based on the torreyanic acid core structure and facile retro Diels-Alder reaction processes and equilibration of diastereomeric 2H-pyrans have been observed. Theoretical calculations of Diels-Alder transition states have been performed to evaluate alternative transition states for Diels-Alder dimerization of 2H-pyran quinone epoxide monomers and provide insight into the stereocontrol elements for these reactions.
Synthesis of (+/-)-puraquinonic acid: an inducer of cell differentiation.
Clive,Sannigrahi,Hisaindee
, p. 954 - 961 (2007/10/03)
Puraquinonic acid (1) was synthesized from 2,5-dimethoxybenzoic acid by way of isochroman 2 and the indanone derivative 3, a Nazarov cyclization being used to construct the five-membered ring.
Stereoelectronic Control of Aromatic Electrophilic Substitution. Importance of Independent Resonance Form Energies
Kruse, Lawrence I.,Cha, Jin K.
, p. 1333 - 1336 (2007/10/02)
Unexpected regiochemistry observed in the electrophilic substitution of polarized aromatic compounds is explained as occurring via a transition state which most closely resembles the valence-bond aromatic resonance form of lowest energy; electrophilic att
