Investigations of the root extract of Dracaena usambarensis Engl. for anticancer principles led to the characterization of one new homoisoflavonoid, (3S)-3,4ʹ,5,6-tetrahydroxy-7-methoxyhomoisoflavanone (1) and a new retrodihydrochalcone, 4ʹ,4-dihydroxy-2,3-dimethoxydihydrochalcone (2) along with six previously reported compounds, including two homoisoflavonoids, 7-O-methyl-8-demethoxy-3-hydroxy-3,9-dihydropunctatin (3) and loureiriol (4); a phenolic amide, 3-(4ʹʹʹ-hydroxyphenyl)-N-[2ʹ-(4ʹʹ-hydroxyphenyl)-2ʹ-methoxyethyl]acrylamide (5); a spirostane, 25S-spirosta-1,4-dien-3-one (6) and two steroids, stigmasterol (7) and stigmasterol 3-O-β-D-glucopyranoside (8). The structures of 1-8 were determined using spectroscopic and spectrometric techniques. The absolute configurations of compounds 1 and 3 were achieved using circular dichroism spectroscopy. Using the resazurin reduction assay and doxorubicin as reference anticancer drug, 1 showed moderate cytotoxicity against drug sensitive CCRF-CEM but was inactive against all the other tested drug sensitive, resistance phenotypes and normal cells. The crude extract and 2-8 were inactive in the preliminary screening against CCRF-CEM and drug resistant CEM/ADR5000 cell lines. Interestingly, the activity of the standard drug, doxorubicin was comparable to those of inactive compounds against CEM/ADR5000 cells. Future studies should focus on structure modifications of 1-3, in order to obtain more potent analogues.

龙血树龙脑根提取物的研究。的抗癌原理导致表征了一种新的同型异黄酮类化合物（3 S）-3,4ʹ，5,6-四羟基-7-甲氧基高异黄酮（1）和新的逆二氢查耳酮4ʹ，4-二羟基-2,3-二甲氧基二氢查耳酮（2）以及六个先前报道的化合物，包括两个同型异黄酮类化合物，7 - O-甲基-8-去甲氧基-3-羟基-3,9-二氢punctatin （3）和卢瑞洛尔（4）；酚酰胺，3-（4′-羟基苯基）-N- [2′-（4′-羟基苯基）-2′-甲氧基乙基]丙烯酰胺（5）；螺环烷25 S-螺环-1,4-二-3-6）和两种类固醇，豆甾醇（7）和豆甾醇3- O- β- D-吡喃葡萄糖苷（8）。的结构1 - 8使用光谱和光谱技术进行了测定。化合物1和3的绝对构型是使用圆二色光谱法获得的。使用刃天青素还原测定法和阿霉素作为参考抗癌药，1显示出对药敏CCRF-CEM的中等细胞毒性，但对所有其他测试的药敏，耐药表型和正常细胞无活性。将粗提取物和2 - 8在针对CCRF-CEM和耐药性CEM / ADR5000细胞系的初步筛选中没有活性。有趣的是，标准药物阿霉素的活性与无活性化合物对CEM / ADR5000细胞的活性相当。未来的研究应集中在结构修改1 - 3中，为了获得更有效的类似物。