4-Demethoxy-4-alkoxydaunorubicins

The synthesis and the antitumor activities of a group of 4-demethoxy-4-alkoxydaunorubicins (VIII) are reported. The new compounds were found to have an activity equal or superior to that of daunorubicin, at somewhat higher doses.     

邻醌鬼臼脂素的合成及其体外抗肿瘤细胞活性

鬼臼脂素类衍生物体内作用模式之一是经氧化生成醌式中间体而进一步发挥作用,本文作者设计合成了４－去氧－４β－酰胺基－３′,4′－邻醌式鬼臼脂素,泱节其体外抑制ＫＢ细胞和Ｌ１２１０白血病细胞活性,并对结果进行了探讨。     

4-去氧-4β-芳甲磺酰胺基-4′-去甲鬼臼脂素的合成及体外抑制肿瘤细胞活性

目的　寻找高效低毒的鬼臼脂素类抗肿瘤药物。方法和结果　设计合成了4-增碳侧链的磺酰胺基鬼臼脂素衍生物(1-15),均为新化合物。并对这些化合物进行了体外抑制KB细胞和L1210白血病细胞活性试验。结论　化合物2,3,8,9,11和12有显著的体外抑制肿瘤细胞活性。     

4-羟基吲哚和4-甲氧基吲哚的合成

目的 寻找操作方便、反应路线短且成本低的工艺路线。方法 通过取代酚的醚化，再在苯环上直接引入腈乙基，然后水解、环合等反应，直接生成吲哚衍生物。结果 采用氢的亲核取代反应(VNS)，直接制得4-羟基吲哚和4-甲氧基吲哚，操作方便，反应路线短且成本较低。结论 4-羟基吲哚和4-甲氧基吲哚的收率分别达57．4％和28．8％，是值得研究推广的新工艺。     

4-Phenylthio-3-pyrrolcarbonsäureester

4-(Phenylthio)-pyrrole-3-carboxylic Acid Esters Dihydro(dimethoxy)methylfurancarboxylic acid esters 4A/B have been applied to the synthesis of the title compounds. With amines as catalysts they react with thiophenols to give the addition products 12a–d , which upon heating with acids eliminate methanol to form the furancarboxylic acid esters 13a–b and 17 , whereas reactions with ammonia or amines lead to the pyrrolecarboxylic acid esters 20a–e . Reactions of 4 with 2-aminothiophenol yield the fused pyrrole and pyrrolidine derivatives 15 and 16 . Compounds 20b and e were transformed to the benzothiopyranopyrrole carboxylic acid esters 23a and b .     

4-酰胺基-4-脱氧-4′-去甲表鬼臼毒素衍生物的合成和抗肿瘤活性

4′-去甲表鬼臼毒素与叠氮酸在三氟化硼乙醚存在下缩合,并经还原得4-氨基-4-脱氧-4′-去甲表鬼臼毒素。该中间体与酸或酸酐反应得相应酰胺化合物24个。经体外筛选,多数化合物抑制L₁₂₁₀和KB细胞活性相当或超过依托泊甙。与相应的醚、酯、胺等类型相比,这一类化合物活性最强。     

Synthetic approaches to peptide analogues containing 4, 4-difluoro-L-proline and 4-keto-L-proline

An improved synthesis of 4, 4-difluoro-L-proline is described. A key step in this synthesis involves the fluorination of Z-4-keto-L-proline benzyl ester, using diethylaminosulfur trifluoride (DAST), to give the corresponding Z-4, 4-difluoro-L-proline benzyl ester. Preparation of dipeptide derivatives containing 4, 4-difluoro-L-proline has been accomplished by initial synthesis of the corresponding 4-keto-L-proline dipeptide derivatives, which were then fluorinated with DAST. A one-step synthesis of Boc-4-keto-L-proline from Boc-4-hydroxy-L-proline by chromium trioxide oxidation is reported. These synthetic procedures should facilitate the preparation of a variety of peptide analogues containing 4, 4-difluoro-L-proline and 4-keto-L-proline.     

Role of cyclooxygenase products in the lung action of leukotrienes A4, B4, C4, D4 and E4

Leukotrienes (LT) LTA4, LTB4, LTC4, LTD4 and LTE4 induced marked contractions of guinea pig lung parenchymal strips mounted in organ baths. These contractions were inhibited differentially (40-50% for LTA4, LTC4, LTD4 and LTE4, and 90% for LTB4) by indomethacin (20 micrograms.ml-1; 55.9 microM). Two novel inhibitors of thromboxane synthetase (OKY-1581 and OKY-046) reduced the myotropic activity of the lung strips and the release of prostaglandins and thromboxanes from the perfused guinea pig lungs stimulated by LTB4 and LTD4. The release of cyclooxygenase products prostaglandin F2 alpha, thromboxane B2 and 12-hydroxyheptadecatrienoic acid by guinea pig lungs following stimulation with LTB4 and LTD4 was also measured by gas chromatography-mass spectrometry. The role of prostaglandins and thromboxanes in the lung actions of leukotrienes was confirmed using a cascade superfusion system and classical organ baths. Although prostaglandins and thromboxanes contribute to the contractile effect of LTB4 on the guinea pig lung whereas they may play a lesser role in the action of the peptidoleukotrienes (approx. 40-50%), stimulation of their release by the peptidoleukotrienes is many times more effective than by LTB4.     

4-烷硫基-4-脱氧-4′-去甲表鬼臼毒素的合成和抗肿瘤活性

对4’-去甲表鬼臼毒素的C₄位进行化学修饰,合成和筛选了10个4-烷硫基-4-脱氧-4’-去甲表鬼臼毒素衍生物以进一步研究C₄位不同的原子和取代基与活性之间的关系及寻找结构简单、活性更强的抗肿瘤新药。4’-去甲表鬼臼毒素与硫醇在三氟化硼·乙醚或三氟乙酸存在下生成相应的硫醚,也可用硫醇与4β-溴-4-脱氧-4’-去甲表鬼臼毒素反应生成相应的硫醚。在体外筛选中,化合物10和12抑制L1210白血病细胞的活性与依托泊甙相当或更强,化合物9,10,12和15抑制KB细胞的活性与依托泊甙相当或更强。     

4-酰硫基-4-脱氧-4-去甲表鬼臼毒素衍生物的合成和抗肿瘤活性

为研究4’-去甲表鬼臼毒素的C₄位不同原子及不同取代基类型同活性之间的关系,寻找活性高、毒性低的抗肿瘤新药,合成了11个4-酰硫基-4-脱氧-4’-去甲表鬼臼毒素,衍生物并进行了抗肿瘤活性试验。4-巯基-4-脱氧-4’-去甲表鬼臼毒素和不同的羧酸在二乙氧基磷酰氰酯存在下得相应的硫酯。该类化合物在L1210白血病细胞和KB细胞的体外抑制试验中普遍表现出抑制活性。化合物10的活性与依托泊甙相当。其余活性比依托泊甙差。与相应的C₄位酰氨基的4’-去甲表鬼臼毒素衍生物相比,活性明显弱。提示氮取代的衍生物活性更好。