N-acyltaurines (NATs) are amides of fatty acids that can be structurally related to endocannabinoids. They show interesting physiological and pharmacological properties. We have synthesized a homologous series of NATs with saturated acyl chains (n = 9–18) and investigated their supramolecular structure and thermotropic phase transitions by powder X-ray diffraction (PXRD) and differential scanning calorimetry (DSC). The d-spacings obtained from PXRD increase linearly with chain length with an increment of ∼0.847 Å per additional CH₂ moiety suggesting that NATs adopt a tilted bilayer structure with similar packing in crystal lattice. Results obtained from DSC studies indicate that the endothermic transition temperature (T_t) of NATs showed a gradually increasing trend with increasing acyl chain length. The enthalpy (ΔH_t) and entropy (ΔS_t) of transition show odd-even alternations with odd-chain compounds having higher values than the even-chain compounds. The critical micellar concentration (CMC) of NATs was determined in water at room temperature by fluorescence spectroscopy by monitoring the spectral changes of 8-anilinonaphthalene-1-sulfonic acid (ANS). The CMCs of NATs were found to decrease with increase in acyl chain length. The present results provide a thermodynamic and structural basis for investigating the interaction of NATs with other membrane lipids and proteins, which in turn can shed light in understanding how they function in vivo (in biological membranes).

N-酰基牛磺酸（NAT）是可以与内源性大麻素在结构上相关的脂肪酸酰胺。它们显示出有趣的生理和药理特性。我们合成了具有饱和酰基链（n = 9-18）的一系列NAT，并通过粉末X射线衍射（PXRD）和差示扫描量热法（DSC）研究了它们的超分子结构和热致相变。从PXRD获得的d间隔随链长线性增加，每增加CH ₂部分约增加0.847Å，这表明NAT采用倾斜的双层结构，在晶格中堆积相似。DSC研究得出的结果表明吸热转变温度（T _t）的NATs显示随着酰基链长度的增加而逐渐增加的趋势。跃迁的焓（ΔH _t）和熵（ΔS _t）表现出奇数-偶数交替，其中奇数链化合物的值高于偶数链化合物。通过监测8-苯胺基萘-1-磺酸（ANS）的光谱变化，通过荧光光谱法在室温下测定水中NAT的临界胶束浓度（CMC）。发现NAT的CMC随着酰基链长度的增加而降低。本研究结果为研究NAT与其他膜脂和蛋白质的相互作用提供了热力学和结构基础，进而可以了解NAT在体内的功能。 （在生物膜中）。