Confirmation of the Structures of Synthetic Derivatives of Migrastatin in the Light of Recently Disclosed Crystallographically Based Claims

In the light of recently disclosed crystallographic studies on migrastatin ketone 2 complex with fascin, the structures of migrastatin ketone 2 and migrastatin ether 4 have been re-evaluated by NMR and X-Ray crystallographic techniques. The results of these studies established the correctness of the previously reported structural assignment and confirm that the "small molecule" co-crystallized in complex with fascin is not the migrastatin ketone, which was provided for the infusion experiment, but rather its stereoisomer.

The migrastatin family: discovery of potent cell migration inhibitors by chemical synthesis

The first asymmetric total synthesis of (+)-migrastatin (1), a macrolide natural product with anti-metastatic properties, has been accomplished. Our concise and flexible approach utilized a Lewis acid-catalyzed diene aldehyde condensation (LACDAC) to install the three contiguous stereocenters and the trisubstituted (Z)-alkene of migrastatin (2 + 3 --> 21). Construction of the two remaining stereocenters and incorporation of the glutarimide-containing side chain was achieved by an anti-selective aldol addition of propionyl oxazolidinone 28 to angelic aldehyde 27, followed by a Horner-Wadsworth-Emmons (HWE) coupling of 32 with glutarimide aldehyde 5. Finally, the assembly of the macrocycle was realized by a highly (E)-selective ring-closing metathesis (35 --> 37). Utilizing the power of diverted total synthesis (DTS), a series of otherwise inaccessible analogues was prepared and evaluated for their potential as tumor cell migration inhibitors in several in vitro assays. These studies revealed a dramatic increase in activity when the natural motif was considerably simplified, presenting macrolactones 45 and 48, as well as macrolactam 55, macroketone 60, and CF(3)-alcohol 71 as promising anti-metastatic agents.

Discovery of Potent Cell Migration Inhibitors through Total Synthesis: Lessons from Structure−Activity Studies of (+)-Migrastatin

Synthesis of highly active migrastatin-based tumor migration cell inhibitors has been accomplished. Our flexible and concise total synthesis of migrastatin has allowed us to explore otherwise inaccessible migrastatin-derived structural motifs. This effort has resulted in the discovery of analogues with tumor cell migration inhibitory activity 3 orders of magnitude higher than that of the natural product.

Reactive dienes: intramolecular aromatic oxidation of 3-(2-hydroxyphenyl)-propionic acids

[reaction: see text] Treatment of 3-(2-hydroxyphenyl)-propionic acids with a hypervalent iodine reagent in the presence of a dienophile initiates a tandem intramolecular aromatic oxidation/Diels-Alder reaction. Herein we report (1) investigations on the scope and limitations of this novel reaction combination and (2) preliminary diastereoselectivity studies using alpha- and beta-substituted acids.

An expeditious approach toward the total synthesis of CP-263,114

[reaction: see text] Assembly of the carbocyclic core of CP-263,114 has been accomplished efficiently and in high yield. Key steps include a phenolic oxidation/intramolecular Diels-Alder sequence, tandem radical cyclization, and the late-stage fragmentation of a densely functionalized isotwistane skeleton.

Evolution of a synthetic approach to CP-263,114

[structure: see text] Three different approaches to the carbocyclic core of CP-263,114 are presented that illustrate a strategic evolution from an oxy-Cope rearrangement to variants of the Wharton fragmentation.