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Electrophile-integrating Smiles rearrangement provides previously inaccessible C4'-O-alkyl heptamethine cyanine fluorophores.

ABSTRACT: New synthetic methods to rapidly access useful fluorophores are needed to advance modern molecular imaging techniques. A new variant of the classical Smiles rearrangement is reported that enables the efficient synthesis of previously inaccessible C4'-O-alkyl heptamethine cyanines. The key reaction involves N- to O-transposition with selective electrophile incorporation on nitrogen. A representative fluorophore exhibits excellent resistance to thiol nucleophiles, undergoes productive bioconjugation, and can be used in near-IR fluorescence imaging applications.

SUBMITTER: Nani RR

PROVIDER: S-EPMC4301176 | biostudies-literature | 2015 Jan

REPOSITORIES: biostudies-literature

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Electrophile-integrating Smiles rearrangement provides previously inaccessible C4'-O-alkyl heptamethine cyanine fluorophores.

Nani Roger R RR Shaum James B JB Gorka Alexander P AP Schnermann Martin J MJ

Organic letters 20150106 2

New synthetic methods to rapidly access useful fluorophores are needed to advance modern molecular imaging techniques. A new variant of the classical Smiles rearrangement is reported that enables the efficient synthesis of previously inaccessible C4'-O-alkyl heptamethine cyanines. The key reaction involves N- to O-transposition with selective electrophile incorporation on nitrogen. A representative fluorophore exhibits excellent resistance to thiol nucleophiles, undergoes productive bioconjugati ...[more]

PMID: 25562683

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