4403-49-0Relevant academic research and scientific papers
Analyzing site selectivity in Rh2(esp)2-catalyzed intermolecular C-H amination reactions
Bess, Elizabeth N.,Deluca, Ryan J.,Tindall, Daniel J.,Oderinde, Martins S.,Roizen, Jennifer L.,Du Bois,Sigman, Matthew S.
supporting information, p. 5783 - 5789 (2014/05/06)
Predicting site selectivity in C-H bond oxidation reactions involving heteroatom transfer is challenged by the small energetic differences between disparate bond types and the subtle interplay of steric and electronic effects that influence reactivity. Herein, the factors governing selective Rh 2(esp)2-catalyzed C-H amination of isoamylbenzene derivatives are investigated, where modification to both the nitrogen source, a sulfamate ester, and substrate are shown to impact isomeric product ratios. Linear regression mathematical modeling is used to define a relationship that equates both IR stretching parameters and Hammett σ+ values to the differential free energy of benzylic versus tertiary C-H amination. This model has informed the development of a novel sulfamate ester, which affords the highest benzylic-to-tertiary site selectivity (9.5:1) observed for this system.
Ground state structures of sulfate monoesters and sulfamates reveal similar reaction coordinates for sulfuryl and sulfamyl transfer
Denehy, Emma,White, Jonathan M.,Williams, Spencer J.
, p. 314 - 316 (2008/02/08)
Structure/reactivity and structure/structure correlations of 5 sulfate monoesters and 11 sulfamate esters determined by low temperature X-ray crystallography reveal similar ground state deformations that suggest similar reaction coordinates for sulfuryl and sulfamyl group transfer. The Royal Society of Chemistry 2006.
Carbonic Anhydrase Inhibitors: Inhibition of Transmembrane, Tumor-Associated Isozyme IX, and Cytosolic Isozymes I and II with Aliphatic Sulfamates
Winum, Jean-Yves,Vullo, Daniela,Casini, Angela,Montero, Jean-Louis,Scozzafava, Andrea,Supuran, Claudiu T.
, p. 5471 - 5477 (2007/10/03)
A series of aliphatic sulfamates and related derivatives incorporating cyclic/polycyclic (steroidal) moieties in their molecules has been synthesized and assayed as inhibitors of the zinc enzyme carbonic anhydrase (CA) and, more precisely, of the cytosolic isozymes CA I and II and the transmembrane, tumor-associated isozyme CA IX. The most potent CA I inhibitor was n-tetradecyl sulfamate and some (substituted)benzyl/phenethyl sulfamates (inhibition constants in the low micromolar range). Against CA II, low nanomolar inhibitors (0.7-3.4 nM) were n-decyl sulfamate and the (substituted)benzyl/phenethyl derivatives mentioned above. Effective CA II inhibition was also observed for the hydroxy/keto derivatives of dehydroepiandrosterone sulfamate. Efficient CA IX inhibitory properties, with inhibition constants in the range of 9-23 nM, were observed for the aliphatic sulfamates C10-C16 (with the most potent inhibitor being the n-dodecyl derivative) and the (substituted)benzyl/phenethyl sulfamates. The inhibition profile of the three investigated isozymes with this type of compound was rather different, allowing us to hope that the preparation of CA IX-selective inhibitors is possible (selectivity ratios toward hCA IX versus hCA II in the range of 5-63 has been observed for some of these compounds, whereas for the clinically used sulfonamides this parameter is in the range of 0.23-0.51). These data are critical for the design of novel antitumor therapies, mainly for hypoxic tumors that overexpress CA IX, which are nonresponsive to radiation or chemotherapy.
Versatile Synthesis of Sulphamate Esters by Phase-transfer Methods
Spillane, William J.,Taheny, Anne P.,Kearns, M. Mary
, p. 677 - 680 (2007/10/02)
The syntheses of sulphamate esters of the general types R1R2NSO3R3, RNHSO3R3, and H2NSO3R3, where R3 may be aliphatic or aromatic, have been achieved in good yield by reaction of the appropriate sulphamoyl chlorides with alcohols and phenols under mild phase-transfer conditions.The present methods have led to generally higher yields, and to shorter reaction times and lower reaction temperatures than were hitherto found necessary.The prior preparation of the alkoxide has also been obviated.Some esters have been rearranged to the isomeric betaines.
