A general and efficient synthetic method for 6-unsubstituted 3,4-dihydropyrimidin-2(1H)-thiones 6 and -ones 7 has been developed. In three-component reactions, the reactivity of reagents serving as the C5–C6 fragment of the dihydropyrimidine ring was compared. The reaction of thiourea or urea 12, aldehydes 13, and ethyl 3-dimethylaminoacrylate 9 in the presence of a catalytic amount of AlCl₃ by heating smoothly proceeds to give 6 and 7 in high yields. A synthetic novelty of our protocol is as follows: 1) Lewis acid-mediated reaction, 2) good to high yields, 3) broad scope as for aldehydes, and ureas. Hitherto unavailable 6-unsubstituted 2-aminodihydropyridimidine 8 has been obtained from the 2-thioxo derivative 6 by a stepwise method involving a substitution reaction with the amine at the 2-position. These 6-unsubstituted compounds 6, 7, and some 6-methyl derivatives 16 were assessed for their antiproliferative effect on the human promyelocytic leukemia cell line, HL-60. The 4-propyl-6-methyl derivative 16b showed relatively strong activity with the IC₅₀ value of 952 nM.

已经开发了用于6-未取代的3，4-二氢嘧啶-2（1H）-硫酮6和-酮7的通用且有效的合成方法。在三组分反应中，比较了用作二氢嘧啶环的C5-C6片段的试剂的反应性。在催化量的AlCl ₃存在下，通过加热使硫脲或尿素12，醛13和3-二甲基氨基丙烯酸乙酯9顺利进行反应，得到6和7高产。我们的方案的合成新颖性如下：1）路易斯酸介导的反应，2）良好至高收率，3）醛和脲的广泛应用。迄今为止，不连续的6-未取代的2-氨基二氢吡啶二甲酰亚胺8是通过逐步法从2-硫代肟衍生物6获得的，该方法涉及与胺在2-位的取代反应。这些6-未取代的化合物6，7，和一些6-甲基衍生物16被评定为在人早幼粒细胞白血病细胞系的抗增殖作用，HL-60。4-丙基-6-甲基衍生物16b具有相对较强的活性，IC ₅₀值为952 nM。