Stereoselective total syntheses of the four stereoisomeric forms of guaiacylglycerol 8-O-4'-coniferyl ether, viz., compounds 1, ent-1, 2, and ent-2, have been established. The key step involves an Evans/Seebach auxiliary-controlled and syn-selective aldol process followed, in the reaction sequences leading to the anti-compounds, by a Mitsunobu reaction involving a benzylic alcohol residue. The ...

The high-yielding synthesis of enantiomerically pure epicatechin gallate analogues where the A and/or B-ring hydroxylation is reduced or altered has been achieved by optimising routes to the catechin stereochemistry. The B-ring analogues were synthesised by using an electrophilic ring closure onto an enantiomerically enriched epoxide as a key step. The A and B-ring hydroxyl-deleted analogues we...

A novel and facile synthesis of 5-hydroxy-4-hydroxymethyl-2-cyclohexenylguanine 1 is described. The key steps involve a Diels-Alder reaction of ethyl (2E)-3-acetyloxy-2-propenoate 2 as dienophile with Danishefsky's diene 3 to build up the six-membered ring skeleton, a Fraser-Reid reductive rearrangement of the adduct using LiAlH(4), and base-moiety introduction using a Mitsunobu reaction. Optic...

The reaction of carboxylic acids with Mitsunobu reagents, prepared by the reaction of triphenylphosphine with dialkyl azodicarboxylates, followed by heating at 180-190 °C under solvent-free conditions, afforded 3-alkyl-5-aryl-1,3,4-oxadiazol-2(3H)-ones. This facile and convenient method readily provides the 1,3,4-oxadiazolone ring systems in good yields using a one-pot protocol starting from th...

lin Measurements: Octanoyl Modification of Ghrelin Is Rapidly Hydrolyzed to Desacyl Ghrelin in Blood Samples, Hiroshi Hosoda, Kentaro Doi, Noritoshi Nagaya, Hiroyuki Okumura, Eiichiro Nakagawa, Mitsunobu Enomoto, Fumiaki Ono, and Kenji Kangawa ( Department of Biochemistry, National Cardiovascular Center Research Institute, and 2 Department of Internal Medicine, National Cardiovascular Center, O...

Combretastatin A-4 is an antitumoral and antitubulin agent that is active only in its cis configuration. In the present manuscript, we have synthesized cis-locked combretastatins embodying a furazan ring (combretafurazans). To achieve this, we have developed a new strategy that exploits the dehydration of vicinal dioximes using the Mitsunobu reaction. Among the advantages of following such a st...

A series of novel 13- to 15-member hydroxyproline-based macrocycles, which contain alkyl-alkyl ether and alkyl-aryl ether moieties, have been synthesized by the strategy of macrocyclization utilising azide-alkyne cycloaddition, Mitsunobu protocol and amide formation. Their anti-tumor activities towards A549, MDA-MB-231 and Hep G2 cells were screened in vitro by an MTT assay. The results indicat...

(2S,4R)- and (2S,4S)-perfluoro-tert-butyl 4-hydroxyproline were synthesized (as Fmoc-, Boc-, and free amino acids) in 2-5 steps. The key step of each synthesis was a Mitsunobu reaction with perfluoro-tert-butanol, which incorporated a perfluoro-tert-butyl group, with nine chemically equivalent fluorines. Both amino acids were incorporated in model α-helical and polyproline helix peptides. Each ...

Title compound was designed to be a black quencher of pyrene fluorescence. It was made amphiphilic to serve as a membrane-bound probe. The synthesis is a two-step procedure. The first step is a Mitsunobu reaction of [{(phenyldiazenyl)phenyl}diazenyl]phenol with 1,2-O-isopropylideneglycerol. The second step is the cleavage of the isopropylidene protecting group. The title compound has the extinc...