First formal synthesis of (+)-nimbidiol. Synthesis, X-ray structure and anticancer activity of a novel ring C aromatic diterpene: dimethyl (+)-podocarpa-8,11,13-triene-12,13-dicarboxylate

A novel ring C aromatic diterpene (4) has been prepared in three steps from natural (+)-manool (1). The structure and anticancer activity data for 4 has been investigated. This key intermediate (4) was easily transformed into 7-deoxo nimbidiol dimethyl ether (8). The present work represents the first formal synthesis of (+)-nimbidiol (10).     

Synthesis of rosane diterpenes

A complete synthesis is reported for the racemic forms of all four possible cis- and trans-B/C-^5(10),15-rosadienes using electrophilic cyclization of their regular A, B-seco precursors in the final step.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 8, pp. 1896–1905, August, 1991.     

Synthesis of 3-Methyl-2,6-dimethylbicyclo[3.3.1]nonane-exo-2,exo-6-diol

In this article, a new 2,6-dimethylbicyclo[3.3.1]nonane-exo-2, exo-6-diol derivative was designed and synthesized. First, the precursor compound (8) was prepared. Key intermediate dione compounds were obtained by reaction with iodomethane followed by hydrolysis and decarboxylation. Finally, methylation of the mixture of compounds 10a and 10b resulted in the formation of the title compound (5).     

An Improved Method of Total Synthesis of 2-Methoxypodocarpane-8,11,13-triene

12-Methoxypodocarpane-8,11,13-triene 1 is the key intermediate for synthesis of some important diterpenoids, such as Ferruginol 21, 6,7-dehydroferruginol 31, sugiol 42, 5-epixanthoperol 53 etc. These compounds posses significant bioactivities, such as fungicidal1, antimicrobial1 and cytotoxic activity2. Some methods of synthesis of the title compound 1 were reported, but the process is laborious and the yield is low. In connection with our effort to discovery and develop new anti-HIV drugs, …     

25,26,27-三失碳-B-高-7-氧-6-酮-5α-胆甾-3α,24-二醇的合成

本文报道以3α-羟基-6-羰基-5α-胆烷酸甲酯(3)为原料经六步反应合成了油菜甾醇类似物25,26,27-三失碳-B-高-7-氧-6-酮-5α-胆甾-3α,24-二醇(9a).总产率14%.9a的促进植物生长作用是24-表油菜甾醇内酯的60%.     

Synthesis of 12-deoxyroyleanone, cryptoquinone, 11,14-dihydroxy-8,11,13-abietatrien-7-one, and related derivatives from dehydroabietic acid

Naturally occurring abietane quinones and hydroquinone, namely, 12-deoxyroyleanone (1a), cryptoquinone (4a), and 11,14-dihydroxyabieta-8,11,13-trien-7-one (5a), together with the epimers of tryptoquinones D (2) and F (3), were first synthesized from dehydroabietic acid (6).     

Synthesis of (+)-6beta-isovaleryloxylabda- 8,13-diene-7alpha,15-diol, a metabolite from Trismusculus reticulatus

[structures: see text] A seven-step synthesis of (+)-6beta-isovaleryloxylabda-8,13-diene-7alpha,15-diol has been achieved starting from (+)-larixol; this allowed determination of the absolute configuration of the metabolite isolated from the mucus of Trimusculus reticulatus.     

Synthesis and Stereochemistry of flavan-3,4-diol diacetates

Two hitherto unknown racemates of flavan-3,4-diol diacetate have been prepared and NMR data now available for the complete set of four racemates establish the stereochemistry of these compounds.     

Synthesis of pyrrolidine and other heterocycles from bu tane-1,4-diol and ethane-1,2-diol

The amination reactions of butane-1,4-diol and ethane-1,2-diol on seven different catalysts obtained by modifying a natural alumosilicate — gumbrin — and a natural zeolite — analcite -with iron and chromium salts, and also by activation with sulfuric acid, have been investigated. The maximum yield of pyrrolidine was obtained in the presence of a catalyst containing ferric oxide on gumbrin.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 7, pp. 937–941, July, 1973.     

Novel Synthesis of Quinoline-7,8-diol Derivative

Quinoline 7,8-diol derivatives can be expected to form metal complexes, and are the moiety of marine alkaloid,which exhibits strong cytotoxic activity against several human tumor. Our synthesis of 6 commences from L-dopa (1)(Scheme 1). Esterification of 2 with methanol and treatment of the resulting ester 3 with trichloroethoxycarbonyl (Troc)chloride yielded the N-protected amino acid ester 4. Treatment of 4 with acrolein in 1.3 mol/L methanolic HCl for 4 d at room temperature yielded the quinoline derivative 5, which was dissolved in 25% aq. HBr and the resulting solution was heated at reflux for 6 h to afford compound 6.     

meso-四苯基-2,3-二氢卟啉-2,3-二醇的合成

研究了一种关于meso-四苯基-2,3-二氢卟啉-2,3-二醇的避免使用昂贵且剧毒的四氧化锇的合成方法,整个合成过程中所用试剂廉价易得,反应操作简单.该合成方法可同时得到顺、反两种目标产物异构体.     

24-亚甲基胆甾-5-烯-3β,19-二醇的合成

从豆甾醇出发,通过10步反应,合成得到具有显著细胞毒活性的24-亚甲基胆甾-5-烯-3β,19-二醇(1),总产率为16%.目标产物1的熔点、[α]值和波谱数据与天然产物一致.化合物1的合成是首次报道,它对人体鼻咽癌(CN2)和胃癌(Mgc803)细胞有显著抑制活性.     

Facile and Simple Synthesis of Ring C Aromatic Diterpenes: Synthesis of (+)-13-Hydroxypodocarpa-8,11,13-triene and (+)-7-Deoxynimbidiol

Alpha alkylation of the nitro group of nitrochromenes was performed by trapping of the nitronate salt generated by NaBH₄ reduction with a Michael acceptor. The adducts were used for the synthesis of spiro-[N-hydroxy]-lactams.     

Synthesis and biological properties of C12,13-cyclopropylepothilone A and related epothilones

Background: The epothilones are natural substances that are potently cytotoxic, having an almost identical mode of action to Taxol^TM as tubulin-polymerization abd microtubule-stabilizing agents. The development of detailed structure-activity relationships for these compounds and the further elucidation of their mechanism of action is of high priority.Results: The chemical synthesis of the C12,13-cyclopropyl analog of epothilone A and its C12,13-trans-diastereoisomer has been accomplished. These compounds and several other epothilone analogs have been screened for their ability to induce tubulin polymerization and death of a number of tumor cells. Several interesting structure-activity trends within this family of compounds were identified.Conclusions: The results of the biological tests conducted in this study have demonstrated that, although a number of positions on the epothilone skeleton are amenable to modification without significant loss of biological activity, the replacement of the epoxide moiety of epothilone A with a cyclopropyl group leads to total loss of activity.     

4-氯-1,7-二羟基二氢化茚的合成及意外醚化反应的研究

以对氯苯酚(8)为原料、三乙胺作缚酸剂，与丙烯酰氯反应生成对氯苯酚丙烯 酸酯(7)，7与A1Ck共热155℃，首先发生Fries重排，然后关环得到4-氯-7-羟基二 氢化茚-1-酮(6)，再用NaBHl／CH_3OH或LiAlH_4／THF还原6的羰基得到4-氯-1，7- 二羟基二氢化茚(5)．条件控制不当易产生两个意外的醚化产物4-氯-1-甲氧基-7- 羟基二氢化茚(9)和自身醚化产物10，9的结构经x射线单晶衍射分析确证，并提出 生成10的可能机理为5的醇羟基极易通过分子内催化形成碳正离子、进而与另一分 子5形成自身醚化产物10．因此，还原反应完成后的后处理应避免长时间放置和加 热，以减少醚化产物的生成．化合物5，9，10均为未见文献报道的新化合物．     

Synthesis and physicochemical properties of cis- and trans-oxolane-3,4-diol derivatives

Conclusions Physicochemical properties of oxolane-3,4-diols, their dinitrates, diacetates, and ditosylates have been determined; the standard enthalpies of combustion and formation have also been measured for the first two series of derivatives.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 4, pp. 874–878, April, 1985.     

Synthesis of 5α-androstan-3β,17β-diol from tigogenin

5α-Androstan-3β,17β-diol (3b-adiol), a known inhibitor of prostate cancer cell growth, was synthesized from tigogenin. Its structure was confirmed by NMR and IR spectroscopy and mass spectroscopy. __________ Translated from Khimiya Prirodnykh Soedinenii, No. 1, pp. 81–82, January–February, 2007.     

24－亚甲基胆甾－4－烯－3β，6α－二醇的结构表征

对采用硼氢化钾－乙醇还原4－烯－3，6－二酮类型的甾酮化合物所获得产物 的结构进行了分析，提出了与文献不同的观点。并通过IR，^1H NMR,^13C NMR等谱 图数据对24－亚甲基胆甾－4－烯－3β，6α－二醇进行了结构表征。     

Synthesis of ether-amines of propane-1,2-diol and their biological activity

An account is given of various routes for the synthesis of ether-amines of propane-1,2-diol from glycerol derivatives. It has been established that this series of compounds exhibits pharmacological activity and also a stimulating or inhibiting effect on the germinating capacity and the energy of germination of the seeds of agricultural crops. A definite relationship has been revealed between the structure and biological activity of ether-amines of propane-1,2-diol. Ether-amines of propanediol and unsymmetrical 1,3-diaminopropan-2-ols, and also their sulfur-containing analogs, containing residues of primary amines or hydrazine are convenient synthons for passing to heterocyclic systems: derivatives of 1,3-ozazolidine, 1,3-thiazolidine, and 3-methyl-5-pyrazolone. The possibility of obtaining new polycyclic systems by diene synthesis from 1,3-oxazolidine and 1,3-thiazolidine derivatives including furfural residues and also from 1,3,4-thiadiazole derivatives, using cyano and thiocyano derivatives of glycerol and thiosemicarbazide is discussed.Tadzhik State University (TGU), Dushanbe. Translated from Khimiya Prirodnykh Soedinenii, No. 5 pp. 649–654, September–October, 1997.