- Preparation and anti-HIV activities of retrojusticidin B analogs and azalignans
-
Ten lignans (2-11) and a series of azalignans including 1-aryl-pyrronaphthalenes 20-24 and 3-N-alkylaminomethyl-1-arylnaphthalenes 25-28, structurally related to two HIV reverse transcriptase inhibitors, retrojusticidin B and phyllamyricin A, were prepare
- Sagar, Kadali S.,Chang, Chia-Chuan,Wang, Wei-Kung,Lin, Jung-Yaw,Lee, Shoei-Sheng
-
p. 4045 - 4054
(2007/10/03)
-
- Oxidative cyclisation of 3,4-dibenzyltetrahydrofurans using ruthenium tetra(trifluoroacetate)
-
A series of trans-3,4-dibenzyltetrahydrofurans has been synthesised and subjected to oxidative cyclisation using ruthenium tetra(trifluoroacetate), affording dibenzocyclooctadiene lignans belonging to the isostegane series, in high yields. Since no evidence was found for the formation of the corresponding stegane isomers it is assumed that the reactions proceed with complete diastereoselectivity.
- Ward, Robert S,Hughes, David D
-
p. 2057 - 2064
(2007/10/03)
-
- Enantiocontrolled Synthesis of Burseran, Brassilignan, Dehydroxycubebin, and Other Tetrahydrofuran Lignans in Both Enantiomeric Forms. Application of Intermolecular Nitrile Oxide Cycloadditions and Lipase Mediated Kinetic Resolutions
-
Several natural and unnatural tetrahydrofuran lignans have been synthesized by a convergent approach.Our methodology utilizes a nitrile oxide cycloaddition to dihydrofuran 8 and an enzymatic resolution of alcohols 11 by lipase PS.The lipase-mediated kinetic resolution of alcohols 11 furnished both enantiomers of the lignan precursors 12 and 14 in high optical purity (>99percent ee).This is followed by a SN2 displacement of tosylates 15 and 18 by α-lithiobenzyl phenyl sulfides.In this manner, both enantiomers of 3,4-dibenzyltetrahydrofuran (17a, 20a), 3,4-bis(3-methoxybenzyl)tetrahydrofuran (17b, 20b), brassilignan (17c, 20c), dehydroxy cubebin (17d, 20d), and burseran (17e, 20e) were synthesized in overall yields of 6-16percent.
- Gaboury, Janet A.,Sibi, Mukund P.
-
p. 2173 - 2180
(2007/10/02)
-
- Synthetic butanolide and tetrahydrofuran lignans with platelet activating factor antagonist activity
-
Several butanolide and tetrahydrofuran lignans were synthesized to be comparatively tested as platelet activating factor (PAF) antagonists.In particular, the influence of the tetrahydrofuranes ether oxygene as compared with the γ-lactone system of butanol
- Coran, SA,Bambagiotti-Alberti, M,Melani, F,Giannellini, V,Vincieri, FF,et al.
-
p. 643 - 650
(2007/10/02)
-
- Oxidative Coupling of Lignans. IV. Monophenolic Oxidative Coupling
-
Oxidative coupling of the monophenolic monoester (6) gives an aryltetralin (12) which is a potential intermediate for the synthesis of clinically active monophenolic lignan lactones.In contrast, oxidative couplings of the monophenols (32) and (35), derived from matairesinol (29), give mixtures of diastereoisomeric cyclooctadiene lignans while 4'-demethyldeoxypodorhizon (26) does not cyclize.These results show that the degree of aromatic substitution in monophenolic diarylbutanes plays an important role in determining the outcome of oxidative coupling.An alternative synthesis of the lactone (57) from piperonal has been investigated.
- Burden, Jonathan K.,Cambie, Richard C.,Craw, Peter A.,Rutledge, Peter S.,Woodgate, Paul D.
-
p. 919 - 933
(2007/10/02)
-