Microwave-accelerated Claisen rearrangements of allyl tetronates and tetramates

Schobert, Rainer; Gordon, G. J.; Mullen, Gillian; Stehle, Ralf

doi:10.1016/j.tetlet.2003.12.024

Cited by 17 publications

(4 citation statements)

References 15 publications

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“…A new lactone 5 of illudin M was prepared by a microwave-assisted domino addition–Wittig olefination of the α-hydroxy ketone fragment of illudin M acetate 3 with the cumulated phosphorus ylide Ph 3 PCCO, , followed by hydrolytic deprotection of the secondary alcohol of 4 (Scheme ). Analogously to the synthesis of 2 , the 1,1′-metallocenedicarboxylates 6 were obtained by Yamaguchi esterification of lactone 5 .…”

Section: Resultsmentioning

confidence: 99%

Cancer Selective Metallocenedicarboxylates of the Fungal Cytotoxin Illudin M

et al. 2011

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The diester 2a obtained from 1,1'-ferrocenedicarboxylic acid and the highly and indiscriminately cytotoxic fungal metabolite illudin M (1) displayed antiproliferative activity at submicromolar IC(50) (72 h) values against a panel of eight cancer cell lines. Compound 2a was about 40 times less toxic than 1 to nonmalignant human foreskin fibroblasts (HF). The analogous bis(illudinyl M) 1,1'-ruthenocenedicarboxylate (2b) exhibited submicromolar IC(50) (72 h) values only against MDA-MB-231 and MCF-7/Topo breast carcinoma and HL-60 leukemia cells. Cytotoxicity studies in the presence of inhibitors of c-Jun N-terminal kinase (JNK) or extracellular signal-regulated kinase (ERK) revealed that the high efficacy of 2a, but not that of 2b, against HCT-116 colon cancer cells depends on active JNK/ERK signaling. A new illudin M lactone 5 was of low anticancer activity, but its ruthenocene diester 6b also reached single-digit micromolar IC(50) (72 h) values in HCT-116, MCF-7, and HL-60 leukemia cells while not affecting HF. Compounds 2a and 6b were tolerated by mice symptom-free at single doses as high as 25 mg/kg body weight, which is evidence for them being chemically stable under physiological conditions. Compound 2a displayed a manageable in vivo toxicity profile when given repeatedly in high doses.

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Section: Resultsmentioning

confidence: 99%

Cancer Selective Metallocenedicarboxylates of the Fungal Cytotoxin Illudin M

et al. 2011

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“…Other examples of this type of transformation include synthesis of ethyl 6-oxo-11-vinyl-hexahydro-1Hpyrido[1,2-b]isoquinolin-11-yl)acetate 27 [71] and , -unsaturated esters 28 and 29, which are valuable precursors of HETEROCYCLIC CHEMISTRY [3,3]-Sigmatropic rearrangement of allyl tetronates 30 (R 1 = H, R 2 = Ar) and the corresponding allyl tetramates (not depicted) gives 3-allyltetronic acids 31 and proceeds within 20-60 min under microwave irradiation (Scheme (8)). Thus, the successful isolation of Claisen intermediates 31 of sigmatropic domino sequences with minimal contamination with Conia products 32 has been reported [73]. Thus, the successful isolation of Claisen intermediates 31 of sigmatropic domino sequences with minimal contamination with Conia products 32 has been reported [73].…”

Section: Claisen Ortho-ester Rearrangementmentioning

confidence: 97%

Microwave-Assisted Claisen and Aza-Claisen Rearrangements

Tymoshenko¹

2008

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“…4,5 Moreover, the combination of these methodologies in a tandem fashion has been reported only rarely, 5 although recent examples have demonstrated the power of the methodology. 6 In order to explore the procedure for olefination/Claisen rearrangement depicted in Scheme 1, we first prepared the novel phosphonate 3. Compound 3 was easily obtained on a multigram scale from diazophosphonate 6 7 and allyl alcohol in a ruthenium-mediated 8 process (Scheme 2).…”

Section: Tandem Horner-wadsworth-emmons Olefination/claisen Rearrangementioning

confidence: 99%