Configuration of the C(20) epimer of 7,8-dihydrobatrachotoxinin A.
نویسنده
چکیده
7,8-Dihydrobatrachotoxinin A is an intermediate in the synthesis of batrachotoxin, the extremely potent venom from the Colombian frog Phyllobates aurotaenia. A crystal structure analysis by x-ray diffraction has confirmed that the intermediate is identical with the natural batrachotoxinin A except for the saturation of the C(7)-C(8) bond. There are seven asymmetric carbon atoms in the molecule. The cis A/B and C/D ring junctions cause the molecule to assume the characteristic shape of cardioactive steroids. A cage is formed from the A-ring, atom C(9), and the O atom that makes the ether linkage between C(3) and C(9).
منابع مشابه
Modification of Na Channels by Synthetic Dihydrobatrachotoxinin A - 20 « - Benzoate
Sodium channels in nodal membrane modified by a synthetic analog of batrachotoxin, 7,8-dihydrobatrachotoxinin A-20a-benzoate, were studied under voltage clamp conditions. The voltage dependence of channel activation was shifted by 70—80 mV towards more negative potentials. Selectivity sequence determined from peak current reversal potenial was as follows: Na:NH 4 :K = 1:0.46:0.23. Our data sugg...
متن کاملStereoselective Property of 20(S)-Protopanaxadiol Ocotillol Type Epimers Affects Its Absorption and Also the Inhibition of P-Glycoprotein
Stereoselectivity has been proved to be tightly related to drug action including pharmacodynamics and pharmacokinetics. (20S,24R)-epoxy-dammarane-3,12,25-triol (24R-epimer) and (20S,24S)-epoxy-dammarane-3,12,25-triol (24S-epimer), a pair of 20(S)-protopanaxadiol (PPD) ocotillol type epimers, were the main metabolites of PPD. Previous studies have shown that 24R-epimer and 24S-epimer had stereos...
متن کاملEffect of Alkyl Substituents on the Hydrogen Bonding and Molecular Structure of Benzophenylhydroxamic Acids Crystal structure of UO2 Complex of p-Isopropylbenzophenylhydroxamic Acid
The effect of alkyl substituents on the C-phenyl and/or the N-Phenyl ring of benzophenylhydroxamic acid on their molecular structure and hydrogen bonding has been investigated. The predominant configuration in CHCl3 is determined by steric and electronic effects. Substituents on the C-phenyl ring favor the cis configuration, while substituents in the N-phenyl ring favor a trans c...
متن کامل6P- TIGLOYLOXYGLECHOMAFURAN A NEW FURANOSESQUITERPENE FROM SALVIA GLUTINOSA
The aerial parts of Salvia glutinosa afforded in addition to lupeol, a - and ? - amyrin a furanosesquiterpene, its structure being established by high field NMR techniques. The relative configuration at C-1, C-10, C-4, C-5 and C-6 of 6?tigloyloxyglechomafuran 1 was determined by the observed NOE'S
متن کاملKinetics and mechanism of intramolecular Cyelization of (R)-undeca-7,8-dien-2-yne "a OFT study
A theoretical study of the kinetic and mechanism of intramoleccha cychcation of (1)-undeca-7,8-dien-2-yne was performed using MT methods at B3LYP and B3PW91 levels of theory using 6-311g, 6-311C.6-31 IGs*, 6-31I+G, 6-31 I4-SG and 6-3114H-Gs* basis seo. Equilibrium molecular geometries andharmonic vibrational frequencies of the reaccint, transition state and product wens calculated. Theconsidere...
متن کاملذخیره در منابع من
با ذخیره ی این منبع در منابع من، دسترسی به آن را برای استفاده های بعدی آسان تر کنید
عنوان ژورنال:
- Proceedings of the National Academy of Sciences of the United States of America
دوره 69 10 شماره
صفحات -
تاریخ انتشار 1972