Werner W, Baumgart J, Burckhardt G, Fleck W F, Geller K, Gutsche W, Hanschmann H, Messerschmidt A, Römer W, Tresselt D
Central Institute of Microbiology and Experimental Therapy, Academy of Sciences of the German Democratic Republic, Jena.
Biophys Chem. 1990 Apr;35(2-3):271-85. doi: 10.1016/0301-4622(90)80015-y.
As an alternative to naturally occurring pyrrolo[2,1-c][1,4]benzodiazepines (e.g., antramycin) which possess properties of DNA alkylation, we have designed several antileukemic chromeno[4,3-b][1,5]benzodiazepine derivatives with potential activity toward leukemia cell membranes and the cyclic nucleotide system. The cis and trans diastereoisomers were characterized by NMR. The absolute configurations of the enantiomers were established by X-ray diffraction and circular dichroism (CD) measurements. By means of absorption spectroscopy and determinations of fluorescence and fluorescence decay, it was found that the cancerostatically active compound (+)(6aR, 13aS)-3,4-dimethoxy-10,11-dimethyl-6,6a,7,8,13, 13a-hexahydrochromeno[4,3-b][1,5]benzodiazepine (ZIMET 54/79) and its biologically inactive (-) enantiomer (ZIMET 55/79) interact with liposomal membranes. At pH values of 6.0 and 7.3 the long-wave absorption bands of these agents showed weak bathochromic and hypochromic effects upon addition of neutral, and positively and negatively charged phosphatidylcholine and phosphatidylcholine/cholesterol liposomes. Such spectral changes are interpreted as resulting from the binding of both agents to phospholipid bilayers. Steady-state determinations using the membrane probe 1-anilino-8-naphthalenesulfonic acid (1,8-ANS) led to the observation of a small decrease in fluorescence intensity in the presence of either agent. Time-resolved measurements demonstrate that the mechanism of action of the agents occurs mainly through the partial displacement of probe molecules from regions of hydrophobic binding to areas of greater solvent accessibility. No significant differences in binding between the cancerostatically active and inactive enantiomers with liposomes (archiral systems) were detectable on the basis of spectrophotometric and fluorescence determinations. Cell membrane bound adenylate cyclase is stimulated by ZIMET 54/79, resulting in an increase of 103% in the level of cAMP in mouse L1210 leukemia cells. On examination of structure-activity relationships, it was found that the biological activity (leukemia L1210, P388, Lewis lung carcinoma, melanoma B16, increase in cAMP) is correlated with the particular configuration (6aR,13aS) and type of substituent at positions 3 and 4 of the benzo ring in the case of alkoxy groups and positions 10 and 11 for methyl groups. No activity was detected toward DNA/RNA using microbial test systems.
作为具有DNA烷基化特性的天然存在的吡咯并[2,1-c][1,4]苯并二氮杂卓（如抗霉素）的替代物，我们设计了几种对白血病细胞膜和环核苷酸系统具有潜在活性的抗白血病色烯并[4,3-b][1,5]苯并二氮杂卓衍生物。通过核磁共振对顺式和反式非对映异构体进行了表征。通过X射线衍射和圆二色性（CD）测量确定了对映体的绝对构型。通过吸收光谱以及荧光和荧光衰减测定发现，具有抗癌活性的化合物(+)(6aR, 13aS)-3,4-二甲氧基-10,11-二甲基-6,6a,7,8,13, 13a-六氢色烯并[4,3-b][1,5]苯并二氮杂卓（ZIMET 54/79）及其无生物活性的(-)对映体（ZIMET 55/79）与脂质体膜相互作用。在pH值为6.0和7.3时，加入中性、带正电和带负电的磷脂酰胆碱以及磷脂酰胆碱/胆固醇脂质体后，这些试剂的长波吸收带显示出微弱的红移和减色效应。这种光谱变化被解释为两种试剂与磷脂双层结合的结果。使用膜探针1-苯胺基-8-萘磺酸（1,8-ANS）进行的稳态测定导致在任一种试剂存在下观察到荧光强度略有下降。时间分辨测量表明，这些试剂的作用机制主要是通过探针分子从疏水结合区域部分位移到溶剂可及性更高的区域。根据分光光度法和荧光测定，未检测到具有抗癌活性和无活性的对映体与脂质体（非手性体系）之间在结合上有显著差异。ZIMET 54/79刺激细胞膜结合的腺苷酸环化酶，导致小鼠L1210白血病细胞中cAMP水平增加103%。在研究构效关系时发现，生物活性（白血病L1210、P388、刘易斯肺癌、黑色素瘤B16、cAMP增加）与特定构型（6aR,13aS）以及苯环3和4位（对于烷氧基）和10和11位（对于甲基）的取代基类型相关。使用微生物测试系统未检测到对DNA/RNA的活性。
