Pharmaceutical and Heterocyclic Compounds Research Laboratory, Department of Chemistry, Iran University of Science and Technology, Tehran, 16846-13114, Iran.
Pharmaceutical and Heterocyclic Compounds Research Laboratory, Department of Chemistry, Iran University of Science and Technology, Tehran, 16846-13114, Iran.
Int J Biol Macromol. 2018 Mar;108:1273-1280. doi: 10.1016/j.ijbiomac.2017.11.050. Epub 2017 Nov 12.
Alginic acid, a widely used naturally occurring carbohydrate which is generally derived from brown seaweeds, can be considered as a bifunctional heterogeneous and green biopolymeric organocatalyst. Alginic acid, without any post-modification with active Bronsted or Lewis acid centers, was found to be a highly active, cost-effective, commercially-available, renewable and recoverable heterogeneous biopolymeric organocatalyst for the expeditious synthesis of polyhydroquinolines (PHQs). Polyhydroquinolines were synthesized from the four-component Hantzsch reaction of ethyl acetoacetate, different aldehydes, ammonium acetate and cyclic 1,3-diones under mild conditions in high to quantitative yields, 75-97%, using alginic acid. Furthermore, alginic acid was found to be reusable for at least 6 consecutive cycles without considerable loss of its catalytic activity.
海藻酸是一种广泛使用的天然存在的碳水化合物，通常从褐藻中提取，可被视为一种具有双重功能的异质和绿色生物聚合物有机催化剂。海藻酸未经任何带有活性布朗斯特或路易斯酸中心的后修饰，被发现是一种高效、经济实惠、商业上可获得、可再生和可回收的异质生物聚合物有机催化剂，可快速合成多氢喹啉（PHQs）。多氢喹啉是通过乙基乙酰乙酸酯、不同醛、醋酸铵和环状 1,3-二酮的四组分 Hantzsch 反应，在温和条件下以高至定量收率（75-97%）合成的，使用海藻酸。此外，海藻酸在至少 6 个连续循环中可重复使用，而其催化活性没有明显损失。
