Studies on Agarofurans Ⅱ.Stereoselective Synthesis of 1α-and 1β-Methyl Agarofuran

1α- and 1β-methyl agarofuran 1 and 2 were stereoselectively synthesized. the key intermediates being synthesized through stereoselective Robinson annulation.The conjugated double bond was redined in an improved way. Alkylation of imine 7 with enone 8, 9, 10 was performed

Studies on Agarofurans Ⅰ. New Synthesis of Nor-Ketoagarofuran and 4-Hydroxydihydroagarofuran

Nor-ketoagarofuran (1), one of the furanoids isolated from grnd Oil, has been Synthesed in a preprative scale in high yield from olefin 3 in 3 steps. Reaction of norketoagarofuran (1) with CH3MgI afforded 4 (2), an another naturallyoccurring tetrahydrofuran derivative.

Studies on Agarofurans VIII. Synthesis of the Metabolites of 4-Butyl-a-agarofuran

The structures of five metabolites (2-6) of agarofuran 1 were confirmed by synthesis. The configuration of the secondary hydroxyl in 7 was determined by Horeau抯 method. The configuration of C-2 in compound 4 and 5 was determined by their stereochemistry and NMR.

Studies on Agarofurans Ⅳ. The Synthesis of 4-Substitutioned Agarofurans

A new synthetic route for α -agarofuran(1b) is described. Several agarofuran derivatives were synthesized in similar way. Derivative 1d was also synthesized in a novel way, in which the substitution at C-4 was performed quantitatively. An ideal condition for cyclization of diol 7 to agarofuran (1) was found.

Studies on Agarofurans VI. The Introduction of Substituents to C-1 and C-2 Positions of Agarofurans

Agarofuranoids with oxygen functions at C-1 and C-2 were synthesized by allylic oxidation. Ketone 2 gave compound 8 and 9 by Grignard reaction. The configuration of C-2 in 8 and 9 were identified by the CD spectroscopy of the benzoate 10.

Studies on Agarofurans V. Studies on the Reductive Ring-Opening of 3,4-Epoxide of Agarofurans

Reduction of epoxides 1, 2, 3 with LAH and LAH/AlCl3 has been studied. The products of reduction with LAH were controlled by Steric and stereoelectronic effects. The reduction with LAH/AlCl3 seemed to involve an intermediate in which one aluminum ion was shared by both oxygen atoms from the epoxide and the tetrahydrofuran ring.

Studies on Agarofurans Ⅲ. The Synthesis of 3-Substituted Agarofurans

14-Nor-3-oxodihydroagarofuran (2) was prepared in high yield. From 2, derivatives12 and 13 were synthesized by Grignard addition. In order to identify the configuration of C-3 in compound 12 and 13, the sterospecific synthesis of compound 12 has been carried out in 5 steps from octalone (14).

α-沉香呋喃衍生物的合成及中枢神经系统活性

目的以沉香精油成分α 沉香呋喃为先导化合物 ,寻找具有神经系统作用的新化合物。方法从天然 (- )香芹酮出发 ,经 7步反应设计合成目标化合物 ,并经光谱方法确证结构。用 4种小鼠行为学药理模型对目标物进行了活性测定。结果合成了 12个 4位取代的α 沉香呋喃衍生物 ,其中 10个为新化合物。药理试验结果表明 :部分该类化合物具有抗焦虑作用和轻度的中枢神经抑制作用。结论 4位烷基碳为 4～ 6个时 ,抗焦虑作用和中枢镇静、催眠作用明显 ,其抗焦虑的有效剂量为 0 5～ 2mg/kg ,小于中枢镇静、催眠的有效剂量 5～ 2 0mg/kg。

卫矛科中的倍半萜成分

卫矛科(Colastraceae)植物在我国分布较广,其中一些种为巾草药所用,很多种民间常作为天然杀虫药。最近,我们从4种卫矛科植物大芽南蛇藤(C. gemmatus Loesen.)、灯油藤(C. paniculatus Willd.)、少果南蛇藤(C. rosthornianus Loesen.)和白杜(E. bungeanus Maxim.)的根皮或其种子中分离得30多个倍半萜化学成分。

GC-MS法测定大鼠血浆中4-丁基-α-沉香呋喃(AF-5)浓度

目的:建立气相色谱-质谱联用检测法测定大鼠血浆中4-丁基-α-沉香呋喃(AF-5)浓度。方法:以氘标记的同位素d4-4-丁基-α-沉香呋喃(d4-AF-5)为内标,血浆经正己烷提取后采用GC-MS法测定AF-5浓度。结果:AF-5在6.25-800μg.L-1范围内线性关系良好,最低检测限为6.25μg.L-1,日内RSD 3.4%-6.9%,日间RSD4.8%-7.0%,方法回收率范围为102.4%-103.3%。结论:在GC-MS选择离子检测中以同位素作分析内标,避免了实验误差、提高了测试精密度。该方法简单实用,适用于AF-5的药动学研究。

用作GC-MS方法内标的氘标记的4-丁基-α-沉香呋喃的合成(英文)

目的合成氘标记的 4 丁基 α 沉香呋喃 ,用作在检测小鼠血药浓度的GC MS方法中的内标物。方法用d3 碘甲烷和硼氘化钠在 4 丁基 α 沉香呋喃中分别引入 4个氘原子。结论通过 9步反应合成了d4 4 丁基 α 沉香呋喃 ,标记纯度为 98%。

A New Sesquiterpene from Celastrus Angulatus

One new sesquiterpene polyol eater named angulatin C was isolated from the root bark of Celastrus angulatus along with a known compound, angulatin B. Their structures were elucidated on the basis of spectral analysis.

沉香呋喃类立体异构体的气相色谱及气-质联用分析研究

采用GC及GC—MS方法,对沉香呋喃类中的三对差向异构体进行了成功的分离鉴定,确定了每对异构体的比例,建立了倍半萜类异构体的分析方法,从而有效地指导了合成反应,加快了合成的进度,为产物合成提供了可靠的依据。

怀念李裕林先生

记述了我国著名有机合成化学家、兰州大学资深教授李裕林先生在祖国的大西北近半个世纪的学术生涯中的主要贡献,其中包括三尖杉酯碱类化合物的半合成,以及生物标志化合物、狼毒素、大环二萜类、桉烷类和沉香呋喃类天然产物的全合成研究。

永瓣藤茎叶中2个新的β-二氢沉香呋喃型倍半萜

目的研究永瓣藤Monimopetalum chinense茎叶的化学成分。方法采用硅胶柱色谱和制备液相色谱技术等多种方法分离永瓣藤的化学成分,并综合运用NMR、HR-ESI-MS等波谱手段鉴定化合物的结构。结果从永瓣藤茎叶甲醇提取物中分离得到2个新的β-二氢沉香呋喃型倍半萜,分别鉴定为1α,6β-二烟酰氧基-9α-乙酰基-β-二氢沉香呋喃(1)、1α,6β-二烟酰氧基-9α-苯甲酰氧基-8α-羟基-β-二氢沉香呋喃(2)。结论化合物1和2均为新化合物,分别命名为永瓣藤素I和永瓣藤素II。

Baker's Yeast Mediated Reduction of Optically Active Diketone

Baker抯 yeast mediated reduction of optically active diketone is described. The two keto groups are efficiently dif-ferentiated and the ee value of the recovered material is considerably raised. It affords highly optically active key intermediates efficiently for the synthesis of natural polyhydroxylated agarofuran products.

沉香中倍半萜类化合物与生物活性研究进展及其质量标志物预测分析

沉香为名贵药材和香料,倍半萜类化合物是沉香的特征成分和主要活性成分,根据其分子骨架可将沉香倍半萜类化合物分为8类。系统地总结了从沉香中分离出的倍半萜类化合物,并对其调节中枢神经系统、抗炎、抗肿瘤细胞毒、抑菌等活性的研究现状进行综述,并在此基础上结合质量标志物(quality marker,Q-Marker)的核心概念,从生源途径、传统药效、传统药性和化学成分等方面对沉香的Q-Marker进行预测分析,α-沉香呋喃、β-沉香呋喃、沉香螺旋醇可作为沉香的Q-Marker,为建立和完善沉香质量标准提供依据,以期为沉香质量的深入研究提供参考。

二氢-β-沉香呋喃型倍半萜类天然产物衍生物的化学研究

二氢-β-沉香呋喃型倍半萜具有化学多样性和生物多样性。对卫矛科卫矛属植物桃叶卫矛的粗提物进行碱水解,获得仅含羟基的二氢-β-沉香呋喃型倍半萜底物,产率高达0.4%。再通过酯化、氧化以及脱羧等反应合成12个衍生物。综合利用1H-NMR、13C-NMR、质谱及X-单晶衍射进行结构鉴定。其中11个为新化合物。此次衍生化探索为今后二氢-β-沉香呋喃型倍半萜的化学研究提供了参考依据。