The unique optical properties of cyanine dyes have prompted their use in numerous applications. Heptamethine cyanines are commonly modified on the methine bridge after synthesis of a meso-chlorine containing cyanine. Herein, a series of heptamethine cyanines containing modified methine bridges were synthesized using substituted dianil linkers. Their optical properties including, molar absorptivity, fluorescence, and quantum yield were measured as well as their hydrophobic effects in polar buffer solution. It was shown that dyes containing cyclopentene in the methine bridge or a phenyl ring in the meso position display increased molar absorptivity while the increased flexibility of the dye containing a cycloheptene in the methine bridge prevented fluorescence.

中文翻译：

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通过取代的二腈接头 将多种取代基引入七甲基花青染料的次甲基桥上†

花青染料的独特光学性质促使其在众多应用中使用。七甲川花青通常的合成后的次甲基桥改性消旋含有花青-氯。本文中，使用取代的二腈连接基合成了一系列含有修饰的次甲基桥的七甲胺花青。测量了它们的光学性质，包括摩尔吸收率，荧光和量子产率，以及它们在极性缓冲溶液中的疏水作用。结果表明，在含有次甲基桥或在苯环环戊染料消旋位置显示增加的摩尔吸光系数而增加含在次甲基桥防止荧光的环庚烯染料的灵活性。