40914-19-0Relevant articles and documents
Revision of the structure and total synthesis of altenuisol
Nemecek, Gregor,Cudaj, Judith,Podlech, Joachim
, p. 3863 - 3870 (2012/09/25)
A total synthesis of the reported structure of altenuisol is described. Comparison of the 1H NMR spectra of the synthesized compound and of the natural product revealed that the originally proposed structure was not correct. Consequently, two constitutional isomers were synthesized. The spectra of one of these compounds - a structure originally proposed as the structure of altertenuol - matched perfectly with the spectra of the natural product. The total synthesis of altenuisol was thus achieved starting with phloroglucinic acid and protocatechuic aldehyde in 10 steps and in 23% yield, where the longest linear sequence consisted of 6 steps. The key step was a Suzuki coupling with concomitant formation of the lactone ring. Whether altertenuol is identical with altenuisol could not be decided. Total synthesis of altenuisol, a minor toxin in ubiquitous Alternaria spp. revealed that the originally proposed structure was not correct. Altenuisol was proved to have an isomeric structure by total synthesis. Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.
Synthesis, structure-activity relationships, and mechanism of action of anti-HIV-1 lamellarin α 20-sulfate analogues
Kamiyama, Haruka,Kubo, Yoshinao,Sato, Hironori,Yamamoto, Naoki,Fukuda, Tsutomu,Ishibashi, Fumito,Iwao, Masatomo
supporting information; experimental part, p. 7541 - 7550 (2012/01/13)
Lamellarin α and six different types of lamellarin α 20-sulfate analogues were synthesized and their structure-activity relationships were investigated using a single round HIV-1 vector infection assay. All lamellarin sulfates having pentacyclic lamellarin core exhibited anti-HIV-1 activity at a 10 μM concentration range regardless of the number and position of the sulfate group. On the other hand, non-sulfated lamellarin α and ring-opened lamellarin sulfate analogues did not affect HIV-1 vector infection in similar concentrations. The lamellarin sulfates utilized in this study did not exhibit unfavorable cytotoxic effect under the concentrations tested (IC50 > 100 μM). Confocal laser scanning microscopic analysis indicated that hydrophilic lamellarin sulfates were hardly incorporated in the cell. HIV-1 Env-mediated cell-cell fusion was suppressed by lamellarin sulfates. These results suggested that lamellarin sulfates have a novel anti-HIV-1 activity besides the previously reported integrase activity inhibition, possibly at a viral entry step of HIV-1 replication.
Synthesis of dictyomedins using phosphazene base catalyzed diaryl ether formation
Ebisawa, Masaru,Ueno, Masahiro,Oshima, Yoshiteru,Kondo, Yoshinori
, p. 8918 - 8921 (2008/03/14)
Dictyomedins isolated from dictyostelium cellular slime molds were synthesized by using diaryl ether derivatives as key intermediates for the cyclization to dibenzofuran followed by palladium catalyzed intramolecular biaryl formation.
