- The design, synthesis and transmembrane transport studies of a biomimetic sterol-based ion channel
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A model sterol-based ion channel was rationally designed and synthesized. The potential ion channel is comprised of a tartrate-derived crown ether to which six steroids are appended. Macromolecule 1a was incorporated into phospholipid vesicles and shown t
- Pechulis, Anthony D.,Thompson, Richele J.,Fojtik, John P.,Schwartz, Herbert M.,Lisek, Carol A.,Frye, Leah L.
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- NEUROACTIVE STEROIDS, COMPOSITIONS, AND USES THEREOF
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Compounds are provided according to Formula (I) and pharmaceutically acceptable salts thereof, wherein Z is a group of the formula (i), (ii), (iii), (iv), or (v), and wherein L1, L2, L3, X1, X2, Y, Rz4, Rz5, Rz6, n, R1, R2, R3a, R3b, R4a, R4b, R6a, R6b, R7a, R7b, R11a, R11b, R14, R17, R19, R20, R23a, R23b, and R24 are as defined herein, and pharmaceutical compositions thereof. Compounds of the present invention are contemplated useful for the prevention and treatment of a variety of CNS-related conditions in mammals.
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Paragraph 00401
(2013/03/26)
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- Coordination of sodium cation to an oxygen function and olefinic double bond to form molecular adduct ion in fast atom bombardment mass spectrometry
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Steroidal allylic alcohols formed Na+ adduct ion peaks [M+Na]+ by the addition of NaCl in FAB mass spectrometry. A comparison of the intensities of the adduct ion peaks of allylic alcohols with those of the corresponding saturated alcohols and olefin suggested that the olefinic double bond and the proximal hydroxyl group had coordinated to Na +. The adduct ion was stable and did not undergo dehydroxylation. We suggest that the Na+ adduct ion will be useful for the molecular weight determination of allylic alcohols which are susceptible to dehydroxylation under FAB mass spectrometric conditions. Na+ adduct ions of α, β-unsaturated carbonyl compounds were also investigated.
- Morisaki, Naoko,Kobayashi, Hisayoshi,Yamamura, Yumiko,Morisaki, Masuo,Nagasawa, Kazuo,Hashimoto, Yuichi
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p. 935 - 940
(2007/10/03)
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- Stereochemistry of Yeast Δ24-sterol methyl transferase
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S-Adenosyl-1-methionine:Δ24-sterol methyl transferase (24-SMT) mediates introduction of the C-28 carbon of yeast sterols. It has been shown that sulfonium analogues of the presumptive cationic intermediates of the methylenation reaction are potent in vivo and in vitro inhibitors of this process. In the presence of these inhibitors, cultures of yeast produced increased proportions of zymosterol, the natural substrate of the enzyme, while proportions of ergosterol and ergostatetraenol were decreased. New C27-sterol metabolites were also found. The in vivo inhibitory power of the analogues [I50 (μM)] was determined from the proportion of C-24 methylated sterols to C-24 nonmethylated sterols in treated cultures to be in the following order: 25-thiacholesteryl iodide (0.07) > 24(S)-methyl-25-thiacholesteryl iodide (0.14) > 24(R)-methyl-25-thiacholesteryl iodide (0.25). kinetic inhibition as revealed by radiolabeled S-adenosyl-1-methionine (SAM), crude enzyme and 25-thiacholesteryl iodide revealed this inhibitor to be uncompetitive with respect to zymosterol and competitive with respect to SAM. The greater inhibitory power of 24(S)-methyl-25-thiacholesteryl iodide compared to 24(R)-methyl-25-thiacholesteryl iodide suggests that methyl donation to Δ24 occurs from the si face. When considered in conjunction with Arigoni's previous work, the present results infer the methylenation mediated by yeast 24-SMT proceeds by alkylation from the si face of Δ24 followed by migration of a hydrogen from C-24 to C-25 across the re face and final loss of a hydrogen from C-28 on the re face.
- Acuna-Johnson, Adriana P.,Oehlschlager, Allan C.,Pierce, Aldona M.,Pierce Jr., Harold D.,Czyzewska, Eva K.
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p. 821 - 832
(2007/10/03)
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- STEROID COMPOUNDS OF MARINE SPONGES. I. STEROLS OF Esperiopsis digitata
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From extracts of the Far Eastern sponge Esperiopsis digitata, by column chromatography on silica gel we have isolated three fractions of steroid compounds.The fractions isolated have been analyzed with the aid of TLC, GLC-MS, PMR, and 13C NMR.The least polar fraction (1) had a Rf value identical with that of cholesterol and represents the total free steroids.After argentation column chromatography, 13 components were identified in it, the main one being cholesterol.The more polar fraction (2) consisted of a combination of 3β-hydroxychol-5-en-24-al and 3β-hydroxy-24-norchol-5-en-23-al.The most polar of the fractions isolated - fraction (3) - consisted of a single component which was identified as cholesta-5,25-diene-3β,24ξ-diol.
- Shubina, L. K.,Makar'eva, T. N.,Boguslavskii, V. M.,Stonik, V. A.
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p. 704 - 709
(2007/10/02)
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