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1.
2.
Fumio Hamada Kyoko Ishikawa Riko Ito Hisanori Shibuya Sanyo Hamai Iwao Suzuki Tetsuo Osa Akihiko Ueno 《Journal of inclusion phenomena and macrocyclic chemistry》1994,20(1):43-51
-Cyclodextrin with two sodium anthranilate moieties (1) has been prepared as a sensor for detecting organic compounds including terpenoids and steroids. Compound1 shows a pure monomer fluorescence whose intensity is increased or decreased upon addition of the guest species examined. In this system, the sodium anthranilate moieties act either as a spacer, which enables the cyclodextrin to form a 1:1 host-guest complex by narrowing the -cyclodextrin cavity, or as a hydrophobic cap.1 recognizes steroids with much higher sensitivity than terpenoids, in which the appended moieties act as a hydrophobic cap for terpenoids and a spacer for steroids, respectively. 相似文献
3.
Xiao-Bai Sun Pei-Hua Zhao Yang-Jun Xu Li-Mei Sun Mei-Ai Cao Cheng-Shan Yuan 《Chemistry of Natural Compounds》2007,43(5):563-566
Investigation of the roots of Polygonum bistorta L. afforded seven compounds including five triterpenoids, a coumarin, and a steroid, the structures of which were identified
by EIMS, 1H NMR, 13C NMR, DEPT, and HMBC experiments. All the compounds have been isolated from Polygonum genus for the first time.
Published in Khimiya Prirodnykh Soedinenii, No. 5, pp. 463–465, September–October, 2007. 相似文献
4.
5.
A new method for the preparation of the synthon (±)-2,6,7,7a-tetrahydro-1β-hydroxy-4-formyl-7aβ-methylindene (1,a) for the
total synthesis of steroids in both (±) and (+) forms, starting from the known β-ketoester, (±)-methyl 1β-t-butoxy-5,6,7,7a-tetrahydro-7aβ-methyl-5-keto-4-indancarboxylate (2,a) has been described. An alternative route to (1,a) has
been investigated. Although the compound, (±)-1β-hydroxy-5,6,7,7a-tetrahydro-7aβ-methyl-5-keto-4-methoxymethylindan (2,b)
could not be prepared, interesting pathways leading to two unexpected products, (±)-5,6,7,7a-tetrahydro-4,7a-dimethyl-5H-indene-1,5-dione
and (±)-2,6-diketo-3-methyltricyclo-(5,2,1,0)decan-8-ol (3 and 4), were encountered during an attempted annelation reaction
of the ketone, N-diethylamino-5-methoxypentan-3-one (6), with 2-methylcyclopentan-1,3-dione (5). Trapping of the intermediate,
(±)-3a,4,5,6,7,7a-hexahydro-3a-hydroxy-4-methylene-7a-methylindene-1,5-dione (7), through the formation of the adduct, (±)-3a,4,5,6,7,7a-hexahydro-3a-hydroxy-4-(1′,
3′-diketo-2′-methylcyclopentano-2′-methylene)-7a-methylindene-1,5-dione (8), established the mechanism of the formation of
the products (3 and 4). 相似文献
6.
Xiao Hong YAN Yue Wei GUO* State Key Laboratory of Drug Research Institute of Materia Medica Shanghai Institutes for Biological Sciences Chinese Academy of Sciences Shanghai 《中国化学快报》2005,16(3)
Marine organisms have been found to be a storehouse of steroids, particularly in term ofunique side-chain structures and unusual functionalization. Marine steroids are oftenfound in highly oxygenated forms and possessing various biological activities1.Previously, we reported the isolation and structural elucidation of three new marinesteroids, nanjiols A-C, which showed cytotoxicity against HL-60 and BEL 7402 celllines, from a soft coral Nephthea bayeri in East China Sea2. In continuation … 相似文献
7.
Jun-Ichi Kikuchi Yukito Murakami 《Journal of inclusion phenomena and macrocyclic chemistry》1998,32(2-3):209-221
Steroid cyclophanes, bearing four bile acid moieties covalently placed on a tetraazaparacyclophane skeleton, were designed and synthesized as artificial cell-surface receptors. Guest-binding behavior of the steroid cyclophanes embedded in a bilayer membrane formed with a synthetic peptide lipid was clarified by means of fluorescence and circular dichroism spectroscopy. We found that the steroid cyclophane effectively bound aromatic guests in both bilayer membranes and aqueous solution. In addition, copper(II) ions acted as a guest species for the steroid cyclophane and a competitive inhibitor toward a NADH-dependent lactate dehydrogenase (LDH). On these grounds, we constituted a supramolecular assembly as an artificial signaling system in combination with the steroid cyclophane, a cationic peptide lipid, and LDH. As a consequence, the steroid cyclophane acted as an effective artificial cell-surface receptor being capable of transmitting an external signal to the enzyme in collaboration with copper(II) ions as a signal transmitter. 相似文献
8.
反式氢化茚酮是全合成甾体的合成子。本文综述了五种合成方法:即分子内 Diels-Alder 反应,分子内 Michael 反应;联合 Cope-Claisen 重排;Lewis 酸催化环合γ,δ-不饱和羰基化合物以及二环庚烷的裂解。 相似文献
9.
Alan M Bond Enrico Mocellin Cherrie B Pascual Panit Wedkanjana Grard Jaouen Siden Top 《应用有机金属化学》1990,4(5):557-568
Electrochemical oxidation of α- and β-diastereomers of a range of steroid hormone receptor marker chromium tricarbonyl complexes, (steroid)Cr(CO)3, have been examined at platinum electrodes in dichloromethane. Data confirm the general nature of previously published conclusions on the oxidation of (arene)Cr(CO)3 complexes (arene = benzene or steroid). That is, with 0.1 M Bu4NPF6 as the electrolyte, and in the absence of nucleophiles, a reversible oneelectron process, (steroid)Cr(CO)3 ? [(steroid)Cr(CO)3]+ + e?, is observed, followed by an irreversible one-electron process at considerably more positive potentials. The reversible half-wave potentials (approximately E°-values) calculated for the [(steroid)Cr(CO)3]+/(steroid)Cr(CO)3 redox couple are shown to be dependent on whether the α- or β-diastereomer is oxidized. Similarly the rate of nucleophilic attack on the 17-electron cation [(steroid)Cr(CO)3]+ by nucleophiles such as ClO, PPh3 and bis(diphenylphosphine)methane confirms a previous observation that the stereochemistry of this class of compound is important with respect to redox, kinetic and hormone receptor properties. The nature of the electrochemical data obtained on the (arene)Cr(CO)3 complexes in the presence of nucleophiles suggests that reactions associated with the nucleophilic attack on the 17-electron cations are complex and that a range of reaction pathways occur simultaneously. Electrochemical studies on the oxidation of (benzene)Cr(CO)2PPh3 and (oestradiol)Cr(CO)2PPh3 confirm some aspects of the proposed mechanisms, although it is clear that a great deal still has to be learned concerning mechanistic aspects of nucleophilic attack on these 17-electron complexes. 相似文献
10.
Tetsuji Kametani Hiroko Kasai Etsuko Sato Toshio Suzuki 《Journal of Chemical Sciences》1988,100(2-3):91-111
For the purpose of organic syntheses of some corynanthe-type indole alkaloids, sesquiterpenes, and steroids, optically active
intermediates cyclopentanone 3-allylalcohol, α-methylene-γ-butylo lactones andtrans-hydrindanone-propionic acid, were synthesized from (R)- and (S)-isopropylideneglyceraldehyde derived fromD-mannitol andLascorbic acid, respectively, utilizing Claisen rearrangement as a key reaction. Actually total syntheses of natural alkaloids,
(-)-antirhine, (+)-dihydroantirhine and (-) dihydrocorynantheol were accomplished. 相似文献