The Structure of Celiprolol

The crystal structure and nuclear magnetic resonance (NMR) spectra and assignments of celiprolol, N-[3-acetyl-4[3-[N-t-butylamino-2-hydroxypropoxy]phenyl]-N, N-diethylurea, are reported. Celiprolol crystallizes in the monoclinic space group, P2_l/a, with a = 9.081(2), b = 13.800(4), and c = 17.471(5) Å and = 95.04(2)°. Structure was solved by direct methods; structure refinement to R of 0.058. Intermolecular hydrogen-bonding in the crystal is discussed. The ¹H, ¹³C, and two-dimensional (2D) NMR spectra of the hydrochloride have been obtained and definitive signal assignments made.     

Assignments of ^1H and ^13C NMR Signals of Mogroside IVa

Aim To investigate the structure of mogroside IVa isolated from traditional Chinese medicine fructus momordicae [fruits of Siraitia grosvenori (Swingle) C. Jeffery] and summarize the NMR characteristics of the structure. Methods Cormnon extraction, separafion and purification methods were used. Various NMR techniques including ^1H NMR,^13C NMR, DEPT, ^1H-^1H COSY, HSQC, HMBC, NOESY and molecular model simulated by comtmter were used to elucidate the structure. Results ^1H and ^13C NMR signals of mogroside IVa were assigned, and spectroscopic basis was obtained for identification of such type of compounds. Conclusion 1D and 2D NMR techniques including ^1H-^1H COSY, HSQC, HMBC, NOESY spectra are powerful tools for structure analysis. The structure determined by NMR methods is identical with energy minimized conformation simulated by computer.     

云南美登木共生放线菌菌株CS产生的新多羟基环己烷衍生物

从云南美登木共生放线菌菌株(Streptomyces sp.)CS的发酵产物中分离得一个新的多羟基环己烷衍生物,并通过波谱学特征鉴定化合物的结构为1-isobutyroxymethyl cyclohex-1(6)-ene-2,3,4,5-tetrol-2-isobutyrate.     

Urinary stability of carboxycyclophosphamide and carboxyifosfamide, two major metabolites of the anticancer drugs cyclophosphamide and ifosfamide

Phosphorus-31 nuclear magnetic resonance spectroscopy was used to evaluate the stability of carboxycyclophosphamide (CXCP) and carboxyifosfamide (CXIF) in human urine at pH 7.0 and 5.5 at 25°, 8°, −20°, and −80 °C. At 25 °C and pH 7.0, CXCP and CXIF are relatively stable (≈10% degradation in 24 h). In contrast, they are much less stable at pH 5.5 (≈80% degradation of CXIF and ≈50% degradation of CXCP in 24 h). The rate of degradation of CXCP and CXIF was a function of the storage temperature of the urine samples but, even at −80 °C, was not negligible: ≈30% degradation for CXCP irrespective of pH and ≈40% and 50% degradation for CXIF at pH 7.0 and 5.5, respectively, after storage for 6 months. CXCP was more stable than CXIF at either pH (7.0 or 5.5) and at all storage temperatures (8°, −20°, or −80 °C) of the urine samples. CXCP and CXIF were more stable at pH 7.0 than at pH 5.5, although this difference fell with decreasing temperatures to be almost negligible at −80 °C. To ensure a true estimate of CXCP and CXIF levels, urine samples must be frozen and stored at −80 °C within a few hours of micturition. CXCP and CXIF assays should also be carried out within 2 months and 1 month of storage, respectively. Received: 13 July 1996 / Accepted: 20 January 1997     

NMR studies of the inclusion complex between β-cyclodextrin and paroxetine

A ¹H and ¹³C NMR study on the inclusion complex of paroxetine with β-cyclodextrin was carried out in order to define the stoichiometry of the association and its strength. Proton and carbon chemical shift measurements of paroxetine and β-cyclodextrin were performed at several molar ratios and temperatures, allowing the determination of a 1:1 stoichiometry and an association constant value of the order of 2 × 10³ for the paroxetine–β-cyclodextrin complex. Overhauser effects in the rotating frame were also measured, and the experimental interproton distance constraints have been used for molecular model building of the complex. The obtained model indicates that the benzodioxolyl moiety of paroxetine is deeply inserted in the cavity of the cylindrical structure of β-cyclodextrin, while the fluoro-phenyl ring lays above the wider rim.     

复方人参注射液核磁共振指纹图谱研究

目的:建立复方人参注射液(人参、陈皮等)的核磁共振指纹图谱,探索质量控制的新方法.方法:运用核磁共振技术对复方人参注射液的中间体和成品进行指纹图谱研究,探索简便易行的指纹图谱分析方法.结果:通过对中间体和注射液的图谱相似度分析,表明工艺流程稳定,重现性良好.结论:核磁共振技术可以作为中成药指纹图谱研究的辅助方法以控制中药质量.     

综合放血法所致血虚证小鼠模型及 四物汤反证的代谢组学研究

目的:通过检测综合放血法所致血虚证及用四物汤干预治疗后小鼠内源性代谢物的变化,确定综合放血法所致血虚证小鼠的血清及组织相关的生物标记物,从代谢组学角度研究血虚证证本质及四物汤的作用机制.方法:C57小鼠30只,按体重随机分为3组:正常对照组、综合放血模型组、四物汤反证组,每组10只.造模10 d后于小鼠股动脉取血,同时取脾脏、胸腺及股骨骨髓,并分别提取血清及组织的脂溶性和水溶性代谢物.用600 MHz超导傅立叶变换核磁共振波谱仪检测,对所得到的氢谱按每段0.01进行分段积分并归一化,用SIMCA-P10.0软件进行主成分分析.结果:与对照组相比,模型组的血清及各组织的内源性代谢物中乳酸、胆碱、牛磺酸、丙氨酸、低密度脂肪酸、甘油、不饱和脂肪酸、肌醉、乙酞乙酸盐、丙氨酸及庄β-羟基丁酸的含量有明显变化,这些变化在四物汤治疗组中有不同程度的回调.上述代谢物可以作为潜在的生物标记物进行相关机制的研究.结论:综合放血法制作的血虚证小鼠的糖有氧氧化受到抑制,无氧酵解减弱,脂肪动员加强,淋巴细胞增殖受到抑制及机体免疫功能受损.四物汤能够对上述血虚证病理结果进行逆转.     

卷柏中双黄酮类化学成分及卷柏属该类化合物的核磁共振特征

目的对卷柏属双黄酮类化合物的核磁共振特征进行归纳。方法应用核磁共振波谱法对卷柏[Selaginellatamariscina(Beauv.)Spring.]50%乙醇提取物中分离得到的5个双黄酮类化合物进行结构鉴定,并结合相关文献对卷柏属双黄酮类化合物的核磁共振特征进行归纳总结。结果首次初步归纳出卷柏属双黄酮类化合物核磁共振碳谱和氢谱的特征。结论通过总结卷柏属双黄酮类化合物的核磁共振特征规律,为快速鉴定该类化合物的结构以及进行核磁数据的归属提供依据。     

Deacetylation of 4-(5-acetylamino-2-furyl)thiazole and formation of 1-(4-thiazolyl)-3-cyano-1-propanone by rat liver tissues

The reductive metabolism of the rat carcinogen 4-(5-nitro-2furyl)thiazole (NFT) to 1-4-thiazolyl)-3-cyano-1-propanone (TCP) is reported. Formation of TCP from NFT involved furan ring fission. This could have occurred through involvement of either aminofuran or N-hydroxylaminofuran as precursors. To examine if 4-(5-amino-2-furyl)thiazole is a precursor for TCP, a stable model compound, 4-(5-acetylamino-2-furyl)thiazole (AAFT), was prepared and subjected to enzymatic deacetylation, using rat liver tissue homogenates. AAFT was synthesized by catalytic hydrogenation of NFT with 5% palladium on activated carbon, followed by acetylation with acetic anhydride. AAFT, a white crystalline powder, melted at 168–170°, had an extinction coefficient of 17.9 mM^?1 cm^?1 at 293 nm in ethyl acetate, and exhibited spectroscopic and mass spectral characteristics consistent with the assigned structure. Incubation with rat liver 10,000 g supernatant preparations resulted in the biotransformation of AAFT as evidenced by a decrease in absorption at 290 nm. Incubation of ¹⁴C-labeled AAFT followed by extraction with chloroform-diethyl ether (1:1) resulted in the recovery of a major portion (56%) of the radioactivity in the organic phase when the label was at the 2-position of the thiazole ring, while the major amount (82%) of radioactivity was recovered in the aqueous phase when the 1-¹⁴C-acetyl group was labeled. The radioactivity from the aqueous phase was extractable into the organic phase following acidification to pH 1, an observation consistent with deacetylation. Furthermore, the deacetylation product exhibited a mass spectrum, and retention times in gas and high pressure liquid chromatography, similar to those of synthetic TCP. These data establish 4-(5-amino-2-furyl)thiazole, derived from AAFT by deacetylation, as a precursor for TCP.     

天山雪莲花主要黄酮类成分初步研究

目的:分析天山雪莲花花药材主要黄酮类成分。方法:植化提取分离纯化鉴定。结果:通过薄层色谱(TLC)、高效液相(HPLC)及核磁共振(NMR)等手段鉴定的总共11个黄酮类化合物分为两类,即黄酮类结构和黄酮醇类型结构,包括6个黄酮及5个黄酮苷化合物。结论:为雪莲药材的质量控制提供支持,提示在相关标准制定工作中可引入相关实验结果对天山雪莲花药花材的质量进行有效控制。