171979-70-7Relevant articles and documents
Atomatic Annulation Strategy for the Synthesis of Angularly-Fused Diterpenoid Quinones. Total Synthesis of (+)-Neocryptotanshinone, (-)-Cryptotanshinone, Tanshinone IIA, and (+/-)-Royleanone
Danheiser, Rick L.,Casebier, David S.,Firooznia, Fariborz
, p. 8341 - 8350 (1995)
The application of a photochemical aromatic annulation strategy in highly efficient total syntheses of several diterpenoid quinones isolated from the traditional Chinese medicine Dan Chen is reported.The pivotal step in each synthesis involves the assembly of the key tricyclic intermediate via the application of a recently developed "second generation" photochemical aromatic annulation method for the construction of highly substituted aromatic systems.In the total synthesis of neocryptotanchinone, the synthesis of the requisite diazo ketone anulation substrate 7 was achieved using paladium-mediated coupling reactions and an intramolecular Friedel-Crafts cyclization to form key carbon-carbon bonds.The pivotal aromatic annulation reaction was then accomplished by irradiating a solution of the diazo ketone 7 and the readily availabe siloxyalkyne 6 in benzene at room temperature.The desired tricyclic phenol 16 was produced in 58-65percent yield and was then converted to (+)-neocryptotanshinone (1) by treatment with tetra-n-butylammonium fluoride in the presence of oxygen.Cyclization to generate (-)-cryptotanshinone (2) was accomplished in high yield by brief exposure of 1 to an ethanolic solution of concentrated sulfuric acid, and dehydrogenation of 2 with DDQ furnished tanshinone IIA (3).As a further demonstration of the utility of the photochemical aromatic annulation strategy in the construction of angularly-fused diterpenes, the total synthesis of (+/-)-royleanone (4) was also investigated.Irradiation of a solution of the diazo ketone 18 and siloxyalkyne 25 produced the tricyclic intermediate 26, which was converted in two steps to royleanone by desilylation and oxidation.
Asymmetric total synthesis of (+)-isocryptotanshinone and formal synthesis of (?)-cryptotanshinone
Shi, Xiang,Liu, Xiaoyu,Yang, Feilong,Wang, Yong,Wang, Zhenwei,Jiao, Xiaozhen,Xie, Ping
, p. 3962 - 3967 (2019)
The first asymmetric total synthesis of (+)-isocryptotanshinone was achieved in 12 linear steps with 12% overall yield from commercially available dihydrobenzopyrone. The key step was a base-mediated cyclization reaction. In addition, the synthetic strate
Antitumor agents 269. Non-aromatic ring-A neotanshinlactone analog, TNO, as a new class of potent antitumor agents
Dong, Yizhou,Shi, Qian,Nakagawa-Goto, Kyoko,Wu, Pei-Chi,Bastow, Kenneth F.,Morris-Natschke, Susan L.,Lee, Kuo-Hsiung
, p. 6289 - 6292 (2009)
Tetrahydroneotanshinlactone (TNT) and tetrahydronaphthalene-1-ol (TNO) derivatives were designed, synthesized, and evaluated for cytotoxic activity. The TNO derivatives were found to be a promising novel class of in vitro antitumor agents. The cyclohexene
A Relay Strategy Actuates Pre-Existing Trisubstituted Olefins in Monoterpenoids for Cross-Metathesis with Trisubstituted Alkenes
Bahou, Karim A.,Braddock, D. Christopher,Meyer, Adam G.,Savage, G. Paul,Shi, Zhensheng,He, Tianyou
, p. 4906 - 4917 (2020/04/10)
A retrosynthetic disconnection-reconnection analysis of epoxypolyenes - substrates that can undergo cyclization to podocarpane-type tricycles - reveals relay-actuated Δ6,7-functionalized monoterpenoid alcohols for ruthenium benzylidene catalyzed olefin cross-metathesis with homoprenyl benzenes. Successful implementation of this approach provided several epoxypolyenes as expected (E/Z, ca. 2-3:1). The method is further generalized for the cross-metathesis of pre-existing trisubstituted olefins in other relay-actuated Δ6,7-functionalized monoterpenoid alcohols with various other trisubstituted alkenes to form new trisubstituted olefins. Epoxypolyene cyclization of an enantiomerically pure, but geometrically impure, epoxypolyene substrate provides an enantiomerically pure, trans-fused, podocarpane-type tricycle (from the E-geometrical isomer).
SUBSTITUTED FNO (2-[FURAN-2-YL] NAPHTHALEN-1-OL) DERIVATIVES AS ANTI-CANCER AGENTS
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Page/Page column 28-29, (2010/08/04)
Compounds of Formulas I are described, along with methods of using such compounds for the treatment of cancer and pharmaceutical formulations thereof.
Biaromatic compounds and pharmaceutical and cosmetic compositions comprising them
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Page column 11, (2010/02/04)
Biaromatic compounds connected by a propynylene or ailenylene bond, corresponding to the formula (I).
