114605-75-3Relevant academic research and scientific papers
Total synthesis of the antitumor antibiotic (±)-streptonigrin: First- and second-generation routes for de novo pyridine formation using ring-closing metathesis
Donohoe, Timothy J.,Jones, Christopher R.,Kornahrens, Anne F.,Barbosa, Luiz C. A.,Walport, Louise J.,Tatton, Matthew R.,O'Hagan, Michael,Rathi, Akshat H.,Baker, David B.
, p. 12338 - 12350 (2014/01/17)
The total synthesis of (±)-streptonigrin, a potent tetracyclic aminoquinoline-5,8-dione antitumor antibiotic that reached phase II clinical trials in the 1970s, is described. Two routes to construct a key pentasubstituted pyridine fragment are depicted, both relying on ring-closing metathesis but differing in the substitution and complexity of the precursor to cyclization. Both routes are short and high yielding, with the second-generation approach ultimately furnishing (±)-streptonigrin in 14 linear steps and 11% overall yield from inexpensive ethyl glyoxalate. This synthesis will allow for the design and creation of druglike late-stage natural product analogues to address pharmacological limitations. Furthermore, assessment of a number of chiral ligands in a challenging asymmetric Suzuki-Miyaura cross-coupling reaction has enabled enantioenriched (up to 42% ee) synthetic streptonigrin intermediates to be prepared for the first time.
Total synthesis of (±)-streptonigrin: De novo construction of a pentasubstituted pyridine using ring-closing metathesis
Donohoe, Timothy J.,Jones, Christopher R.,Barbosa, Luiz C. A.
supporting information; experimental part, p. 16418 - 16421 (2011/11/29)
The synthesis of the potent antitumor agent (±)-streptonigrin has been achieved in 14 linear steps and 11% overall yield from ethyl glyoxalate. The synthesis features a challenging ring-closing metathesis reaction, followed by elimination and aromatization, to furnish a key pentasubstituted pyridine fragment.
BIARYL PHOSPHODIESTERASE 1NHIBITORS
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Page/Page column 53, (2012/08/29)
Novel biaryl compounds with phosphodiesterase inhibitory activity of the general formula (I), wherein R1, R2, R3, X, Y, Z1, Z2, Z3, and Z4 have the meanings defined herein, as well as their use as therapeutic agents in the treatment of inflammatory diseases and conditions
Regioselective monobromination of free and protected phenols
Pla, Daniel,Albericio, Fernando,Alvarez, Mercedes
, p. 1921 - 1924 (2008/02/06)
A comparative study of the advantages of using THF compared with DMF in regioselective monobromination reactions of highly activated polyphenols, their ethers, and their tert-butyl carbonate derivatives under mild conditions is described. Bromination with
Regioselectivity in the Reactions of Methoxydehydrobenzenes with Furans. Part 2. 2-Methoxyfuran and Methoxydehydrobenzenes
Giles, Robin G. F.,Hughes, Andrew B.,Sargent, Melvyn V.
, p. 1581 - 1587 (2007/10/02)
Acid-induced ring opening of adducts of furan and methoxydehydrobenzenes gives the naphthalenols derived from the more stable carbocation.The cycloadditions of methoxydehydrobenzenes containing a 3-methoxy group and 2-methoxyfuran are highly regiospecific
The Structure and Synthesis of the Novel Orchid Pigments Dengibsin and Dengibsinin
Sargent, Melvyn V.
, p. 2553 - 2564 (2007/10/02)
The structures of the orchid pigments dengibsin and dengibsinin have been revised to 2,5-dihydroxy-4-methoxy-9H-fluoren-9-one (4) and 3,5-dihydroxy-2,4-dimethoxy-9H-fluoren-9-one (5).The synthesis of these compounds is described.It has been found that 2'-methoxybiphenyl-2-carboxylic acids, on treatment with trifluoroacetic anhydride or oxalyl chloride, undergo cyclization giving 6H-dibenzopyran-6-ones.
