Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts:   Target Concepts:
Query: CAS:22373-09-7 (cholestane)
 779 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Seven new steroidal glycosides named pentandrosides A(1)-G(7) were isolated from the EtOH extract of the aerial parts of Tribulus pentandrus. Pentandrosides A(1)-E(5) possess cholestane aglycones, pentandroside F(6) a furostan-type aglycone and pentandroside G(7) an unusual acyloxypregnane aglycone probably derived from the degradation of a furostan skeleton. Structure elucidation of 1-7 was accomplished through the extensive use of 1D- and 2D NMR experiments including 1H-1H (DQF-COSY, 1D-TOCSY) and 1H-13C (HSQC, HMBC) spectroscopy along with ESIMS and HRESIMS.
 ...
PMID:Steroidal saponins from the aerial parts of Tribulus pentandrus Forssk. 1550 Dec 64

A novel polyhydroxyl sterol (1) along with one known polyhydroxyl sterol (2), and two known monoglycosides, asterosaponin P1 (3) and its desulfated monoglycoside (4), have been isolated from the whole bodies of a common Pacific starfish Asterina pectinifera. The structure of the new polyhydroxyl sterol was determined as 15beta,16beta-isopropylidenedioxy-5alpha-cholestane-3beta,4beta,6alpha,7alpha,8,26-hexaol by spectroscopic methods, including FABMS, HR-FABMS, 1D and 2D NMR techniques.
 ...
PMID:A novel polyhydroxyl sterol from Asterina pectinifera. 1562 98

Diacronema sp. was cultured and its sterols were separated by column chromatography on silica gel. The new sterol 24-ethyl-4alpha-methyl-cholestane-3,20-diol (1) was characterised by NMR and MS spectrometry, as well as (22E)-24-ethyl-4alpha-methyl-5alpha-cholest-22-en-3beta-ol (2) and beta-sitosterol, the major components of the sterol fractions. Neither the biosynthetic origin of the new dihydroxysterol nor its role in the biochemistry of Diacronema is known.
 ...
PMID:A new dihydroxysterol from the marine phytoplankton Diacronema sp. 1589 86

The magnetic alignment behavior ofbicelles (magnetically alignable phospholipid bilayered membranes) as a function of the q ratio (1,2-dihexanoyl-sn-glycerol phosphatidylcholine/1,2-dimyristoyl-sn-glycerol phosphatidylcholine mole ratio) and temperature was studied by spin-labeled X-band electron paramagnetic resonance (EPR) spectroscopy and solid-state 2H and 31P NMR spectroscopy. Well-aligned bicelle samples were obtained at 45 degrees C for q ratios between 2.5 and 9.5 in both the EPR and NMR spectroscopic studies. The molecular order of the system, S(mol), increased as the q ratio increased and as the temperature decreased. For higher q ratios (> or = 5.5), bicelles maintained magnetic alignment when cooled below the main phase transition temperature (approximately 30 degrees C when in the presence of lanthanide cations), which is the first time, to our knowledge, that bicelles were magnetically aligned in the gel phase. For the 9.5 q ratio sample at 25 degrees C, S(mol) was calculated to be 0.83 (from 2H NMR spectra, utilizing the isotopic label perdeuterated 1,2-dimyristoyl-sn-glycerol phosphatidylcholine) and 0.911 (from EPR spectra utilizing the spin probe 3beta-doxyl-5alpha-cholestane). The molecular ordering of the high q ratio bicelles is comparable to literature values of S(mol) for both multilamellar vesicles and macroscopically aligned phospholipid bilayers on glass plates. The order parameter S(bicelle) revealed that the greatest degree of bicelle alignment was found at higher temperatures and larger q ratios (S(bicelle) = -0.92 for q ratio 8.5 at 50 degrees C).
 ...
PMID:Magnetically aligned phospholipid bilayers with large q ratios stabilize magnetic alignment with high order in the gel and L(alpha) phases. 1603 38

Six steroidal glycosides (1-6) were isolated from the aerial parts of Tribulus alatus Del. (Zygophyllaceae), together with one known cholestane, one spirostane, and six flavonol glycosides. Among them, 1 and 2 possess a furostane-type aglycone, 3 and 6 a cholestane structure, and 4 and 5 a spirostane skeleton. Their structural elucidation was accomplished by extensive spectroscopic methods including 1D ((1)H, (13)C, (13)C DEPT, TOCSY, ROESY) and 2D NMR experiments (DQF-COSY, HSQC, HMBC) as well as ESI-MS analysis.
 ...
PMID:Steroidal saponins from the aerial parts of Tribulus alatus Del. 1663 Dec 16

Three new polyoxygenated steroids, named 3beta,7alpha,9alpha-trihydroxy-cholestan-6-one (1), 3beta,5alpha,6beta-trihydroxycholestan-1-one (2) and cholestane-3beta,5alpha,6beta,11beta-tetrol (3), along with four known steroids (4-7) were isolated from the South China Sea gorgonian Echinogorgia aurantiaca. The structures of 1-3 were established by extensive spectroscopic analysis, including 1D and 2D NMR data.
 ...
PMID:New polyoxygenated steroids from the South China Sea gorgonian Echinogorgia aurantiaca. 1688 75

It has been empirically known that cholesterol largely increases the viscosity of oleic acid. To clarify the mechanism of the effect of cholesterol on the intermolecular and the intramolecular (segmental) movements of oleic acid in the liquid state, we measured density, viscosity, IR, 1H NMR chemical shift, self-diffusion coefficient, and 13C NMR spin-lattice relaxation time for the liquid samples of oleic acid containing a small amount of cholesterol. Furthermore, the above measurements were also carried out for the samples of oleic acid containing a small amount of cholestanol, cholestane, cholesteryl oleate, ethanol, or benzene. Cholesterol, possessing one OH group and one double bond in its molecular structure, largely increased the viscosity and reduced the self-diffusion and the intramolecular movement of oleic acid. Cholestanol, possessing one OH group but not a double bond, and cholesteryl oleate, not possessing an OH group, also reduced the self-diffusion and the intramolecular movement; cholestane, not possessing an OH group, slightly reduced the self-diffusion and the intramolecular movements. In contrast with these sterols, ethanol and benzene reduced the viscosity and increased the self-diffusion and the intramolecular movements. In addition, cholesterol and ethanol, both having one OH group, promoted the upfield shift of the 1H NMR signal of the carboxyl group of oleic acid; IR difference spectra for the cholesterol/oleic acid system quite resemble those for the ethanol/oleic acid system. These results suggest that oleic acid makes a complex with cholesterol as well as with ethanol. On the basis of the formation of the complex, we have revealed the role and the functional mechanism of cholesterol to the intermolecular and the intramolecular movements of oleic acid in the liquid state.
 ...
PMID:Effect of cholesterol and other additives on viscosity, self-diffusion coefficient, and intramolecular movements of oleic acid. 1724 17

The rhizomes of Convallaria majalis have been analyzed for their steroidal glycoside constituents, resulting in the isolation of a new 5beta-spirostanol triglycoside, named convallasaponin A, along with two known cardenolide glycosides and a known cholestane glycoside. The structure of convallasaponin A was determined on the basis of extensive spectroscopic analysis, including 2D NMR data, and the results of hydrolytic cleavage. The cardenolide glycosides showed tumor specific cytotoxic activity.
 ...
PMID:Convallasaponin A, a new 5beta-spirostanol triglycoside from the rhizomes of Convallaria majalis. 1726 12

A mixture of a pair of stereoisomeric new spirostanol saponins (1a and 1b) and a new cholestane saponin (2) were isolated from the rhizome of Paris pollyphylla Smith var. yunnanensis. Their structures were elucidated as (25R)-spirost-5-en-3beta, 7beta-diol-3-O-alpha-L-arabinofuranosyl-(1 --> 4)-[alpha-L-rhamnopyranosyl-(1 --> 2)]-beta-D-glucopyranoside (1a), (25R)-spirost-5-en-3beta, 7alpha-diol-3-O-alpha-L-arabinofuranosyl-(1 --> 4)-[alpha-L-rhamnopyranosyl-(1 --> 2)]-beta-D-glucopyranoside (1b) and 26-O-beta-D-glucopyranosyl-(25R)-Delta(5(6), 17(20))-dien-16, 22-dione-cholestan-3beta, 26-diol-3-O-alpha-L-arabinofuranosyl-(1 --> 4)-[alpha-L-rhamnopyranosyl-(1 --> 2)]-beta-D-glucopyranoside (2) by a combination of HR-ESI-MS, FAB-MS, 1D and 2D NMR techniques (including (1)H-NMR, (13)C-NMR, (1)H--(1)H COSY, HSQC, HMBC and NOESY).
 ...
PMID:Three new steroidal saponins from the rhizome of Paris polyphylla. 1763 16

Seven sulfated polyhydroxysteroids were isolated from the Far East starfish Pteraster obscurus and the ophiura (snake star) Asteronyx loveni (collected in the Sea of Okhotsk) and characterized: disodium and sodium salts of (20R)-24-methyl-2beta-hydroxycholesta-5,24(28)-diene-3alpha,21-diyl disulfate, (20R)-5alpha-cholestane-3beta,21-diyl disulfate, (20R)-3beta-hydroxy-5alpha-cholestan-21-yl sulfate, (20R)-cholest-5-ene-3beta,21-diyl disulfate, (20R)-2beta-hydroxycholest-5-ene-3alpha,21-diyl disulfate, (20R)-cholest-5-en-3beta-yl sulfate, and (20R)-5alpha-cholestan-3beta-yl sulfate. The first four compounds turned out to be new, whereas the others were identical to the known compounds. Structures of the isolated steroids were identified by two-dimensional NMR spectroscopy and other physicochemical methods. The compounds isolated from starfish are structurally similar to typical ophiuroid metabolites, which support the opinion of some taxonomists that starfish and ophiuroids are phylogenetically related classes.
 ...
PMID:[Steroid compounds from the Far East starfish Pteraster obscurus and the ophiura Asteronyx loveni]. 1768 94


<< Previous 1 2 3 4 5 6 7 8 9 10 Next >>