2426-52-0Relevant academic research and scientific papers
Interaction of Remote Functional Groups (Amide and Amine) in Steroidal Compounds After Electron Ionization
Longevialle, Pierre,Bouchoux, Guy,Hoppilliard, Yannik
, p. 527 - 536 (1990)
Electron impact ionization of steroidal compounds with two differently substituted functional groups (amide and amine) at remote positions leads to the interaction of these groups in ion-neutral complexes after the detachment of one of them.Two situations may be encountered, depending on which group is more easily detached from low-energy parent ions: (i) when the formation of the immonium ion is preferred, a very efficient proton transfer to the amide is observed leading to abundant +. and subsequent daughter ions; (ii) when the detachment of the amide is preferred, hydrogen exchanges occur with the amine group, and fragment ions may be observed resulting from the addition of both groups in a proton-bound structure.
NOVEL METHOD FOR THE DIASTEREOSELECTIVE PRODUCTION OF A CHIRAL PRIMARY AMINE ON A STEROID
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Page/Page column 3, (2010/04/23)
The invention relates to a diastereoselective method for obtaining a primary amine on a steroid, comprising the reduction of an oxime by lithium in ammonia at a low temperature in an ether/alcohol mixture.
Oligonucleotide having enhanced binding affinity
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, (2008/06/13)
The present invention relates to an oligonucleotide or analog thereof conjugated to a molecule comprising a structure, which structure (a) is of substantially fixed conformation; (b) contains, is directly attached to, or is attached to a carbon atom that is directly attached to, an first amine; and (c) contains, is directly attached to, or is attached to an atom that is directly attached to a phosphate, a second amine, or a cationic sulfur. In a preferred embodiment, the structure consists of at least a nonaromatic cyclic portion or substituted derivative thereof. In a specific embodiment, the structure is a nonaromatic cyclic compound. In another embodiment, the molecule is a steroid. In yet another particular aspect, the structure is an aromatic compound. In another embodiment, the structure can bind to a nucleic acid sequence in a nonintercalative manner. The invention also relates to a conjugate comprising a steroid or substituted derivative thereof containing, or attached directly or through a carbon atom to, an amine, which steroid or substituted derivative is conjugated to at least one hydrogen-phosphonate and a cation; such a conjugate may be used as an intermediate in synthesis. The oligonucleotide conjugates of the invention can have a number of uses. For example, the conjugates may be used for diagnostic purposes by detecting a nucleic acid sequence.
A water soluble dimeric steroid with catalytic properties. Rate enhancements from hydrophobic binding
Guthrie, J. Peter,Cossar, John,Dawson, Brian A.
, p. 2456 - 2469 (2007/10/02)
Dimeric steroids can be formed by reductive amination of terephthalaldehyde with 3-amino steroids using cyanoborohydride.An amino group in the 11 β-position can be blocked using a formyl group, and this can be removed by acid hydrolysis after dimerization.Trifluoroacetyl is not a suitable blocking group; although it can be removed by acid hydrolysis from monomeric steroids, it was only removed from the dimer under forcing conditions which caused degradation.The dimeric steroid is a catalyst for the hydrolysis of arylpropionate esters with good leaving groups.Acylation is markedly accelerated by hydrophobic binding of the aryl group of the substrate to the steroids.Rate enhancements, relative to imidazole, of up to 5.5 x 102 were obtained, and analysis of the data shows that the potential rate enhancement is 1.1 x 105.The magnitude of the hydrophobic binding is consistent with what was seen with earlier catalysts.Aggregation, even at very low concentrations, was a problem with anionic substrates.
