1195-13-7Relevant academic research and scientific papers
Synthesis and biological evaluation of pyrrolinic isosteres of rilmenidine. Discovery of cis-/trans-dicyclopropylmethyl-(4,5-dimethyl-4,5-dihydro-3H-pyrrol-2-yl)- amine (LNP 509), an I1 imidazoline receptor selective ligand with hypotensive activity
Schann,Bruban,Pompermayer,Feldman,Pfeiffer,Renard,Scalbert,Bousquet,Ehrhardt
, p. 1588 - 1593 (2001)
To find new compounds selective for purported I1 imidazoline receptors (I1Rs), over I2 imidazoline binding sites (I2BS) and α2-adrenoceptors (α2ARs), a series of pyrrolinic isosteres of rilmenidine has been prepared and their biological activity at I1Rs, I2BS, and α2ARs evaluated. This isosteric replacement provided us with compounds which still bound to I1Rs but not to I2BS nor to α2-ARs. A limited structure-affinity relationship was generated around the heterocyclic moiety of these ligands. One compound in this series, LNP 509 (1e) [cis-/trans-dicyclopropylmethyl-(4,5-dimethyl-4,5-dihydro-3H-pyrrol-2-yl) -amine], had no detectable affinity at α2ARs yet was capable of lowering blood pressure after central administration. These pyrrolinic analogues constitute a new chemical class of imidazoline related compounds with high selectivity for the I1Rs. They could be used as new tools in the study of I1Rs and in the conception of new centrally acting hypotensive drugs.
Stereodivergent Synthesis of Two Novel α-Aminophosphonic Acids Characterised by a cis-Fused Octahydroindole System
Arizpe, Alicia,Sayago, Francisco J.,Jimenez, Ana I.,Ordonez, Mario,Cativiela, Carlos
, p. 3074 - 3081 (2011)
The synthesis of two new α-aminophosphonic acids, namely (2S*,3aS*,7aS)- and (2R*,3aS*,7aS)-octahydroindole-2- phosphonic acids, is described. They are analogues of phosphoproline with a cyclohexane ring fused to the pyrrolidine moiety. The ring junction has cis stereochemistry in both cases, but the two compounds differ in the relative orientation of the cyclohexane and phosphonate moieties. The two amino acids were prepared from a common starting material following stereodivergent routes that provide the desired stereoisomer with complete stereocontrol. The relative configurations of the compounds synthesised were confirmed by X-ray diffraction analysis. Two analogues of phosphoproline with a cyclohexane ring fused to the pyrrolidine moiety have been synthesised. They differ in the stereochemistry at the α-carbon atom and have been prepared, with complete stereocontrol, following stereodivergent routes from a common precursor.
Stereoselective Preparation of Bicyclic Lactams by Copper- or Ruthenium-catalysed Cyclization of N-Allyltrichloroacetamides: A Novel Entry to Pyrrolidine Alkaloid Skeletons
Nagashima, Hideo,Ara, Ken-ichi,Wakamatsu, Hidetoshi,Itoh, Kenji
, p. 518 - 519 (1985)
Cyclization of certain N-allyltrichloroacetamides provides a stereoselective preparative method for several bicyclic lactams.
One-Pot Transformation of Simple Furans into Octahydroindole Scaffolds
Kalaitzakis, Dimitris,Triantafyllakis, Myron,Ioannou, Georgios I.,Vassilikogiannakis, Georgios
, p. 4020 - 4023 (2017)
A highly efficient and general singlet-oxygen-initiated one-pot transformation of readily accessible furans into octahydroindole scaffolds has been developed.
Diastereoselective Rhodium-Catalyzed Hydrogenation of 2-Oxindoles and 3,4-Dihydroquinolones
Schiwek, Christian H.,Jandl, Christian,Bach, Thorsten
supporting information, p. 9468 - 9472 (2020/11/30)
The benzene ring of indolin-2-ones (2-oxindoles) and 3,4-dihydroquinol-2-ones was converted to a saturated cyclohexane ring by hydrogenation in the presence of the rhodium complex Cy(CAAC)Rh(cod)Cl. The stereoselectivity of the process was found to be high with respect to both external substituent R1 within the saturated part of the heterocyclic ring and substituent X on the benzene ring. Twenty-one hexahydroindolin-2(3H)-ones (70-99% yield, dr = 83/17 to >99/1) and twelve octahydro-2(1H)-quinolinones (87-96% yield, dr = 64/36 to >99/1) were obtained with the major diastereoisomer exhibiting the hydrogen atoms in an all-cis arrangement. The high tolerance toward functional groups and the compatibility with existing stereogenic centers are key features of the hydrogenation protocol presented here.
Synthetic Utility of N-Benzoyloxyamides as an Alternative Precursor of Acylnitrenoids for γ-Lactam Formation
Huh, Soohee,Hong, Seung Youn,Chang, Sukbok
, p. 2808 - 2812 (2019/04/17)
Described herein is the development of a new entry of acylnitrenoid precursors for γ-lactam synthesis via an intramolecular C-H amidation reaction. Upon Ir catalysis, N-benzoyloxyamides serve as efficient substrates to afford 5-membered amides. Mechanistic studies revealed that the generation of a putative Ir-carbonylnitrenoid via N-O bond cleavage is facilitated by the chelation of countercations. This protocol offers a convenient and step-economic route to γ-lactams starting from the corresponding carboxylic acids.
Highly Selective Hydrogenation of Aromatic Ketones and Phenols Enabled by Cyclic (Amino)(alkyl)carbene Rhodium Complexes
Wei, Yu,Rao, Bin,Cong, Xuefeng,Zeng, Xiaoming
supporting information, p. 9250 - 9253 (2015/08/11)
Air-stable Rh complexes ligated by strongly σ-donating cyclic (amino)(alkyl)carbenes (CAACs) show unique catalytic activity for the selective hydrogenation of aromatic ketones and phenols by reducing the aryl groups. The use of CAAC ligands is essential for achieving high selectivity and conversion. This method is characterized by its good compatibility with unsaturated ketones, esters, carboxylic acids, amides, and amino acids and is scalable without detriment to its efficiency.
Preparation of γ- and δ-lactams by ring closure of β,γ-unsaturated amides using trifluoromethanesulfonic acid
Marson, Charles M.,Fallah, Asad
, p. 293 - 296 (2007/10/02)
γ-Lactams and δ-lactams can be prepared by the reaction of β,γ-unsaturated amides with trifluoromethanesulfonic acid.
RADICAL CYCLIZATION OF ALLYLIC HALOACETAMIDES A ROUTE TO CIS-FUSED 2-PYRROLIDONES AND PIPERIDONES
Stork, Gilbert,Mah, Robert
, p. 723 - 727 (2007/10/02)
A variety of N-protected haloacetamides undergo efficient radical cyclization to produce N-protected lactams.The protecting groups can be removed under a range of different conditions.
Azabicyclo Chemistry. 7. Ultra-High Field (600 MHz) NMR Spectroscopy in Solving Conformational Problems: cis-Octahydroindoles
Mokotoff, Michael,Hill, Scott T.
, p. 65 - 71 (2007/10/02)
Studies using ultra-high field (600 MHz) nmr spectroscopy has allowed us to assign the conformational preference of cis-octahydroindoles, including the position of their nitrogen lone-pair electrons.Lithium aluminium hydride reduction of cis-octahydroindol-2-one (4) gave cis-octahydroindole (5a) which showed three distinct nmr resonances, the C7a proton at δ 3.04 (apparent q, J = 5.3 Hz) and the two C2 protons at δ 3.10 and 2.94.The latter two resonances were absent in the C2 deuterated compound 5b.Deuteromethylation of 5a, via a urethane intermediate, gave 1-deuteromethyl-cis-octahydroindole (8a) which showed resonances at δ 3.12 for the α-faced C2 proton, the β-faced C2 proton at δ 2.17, and the C7a proton at δ 2.15.The resonances at δ 3.12 and 2.17 are absent in the corresponding C2 deuterated compound 8b, and the C7a remains as a doublet of triplets (d, J = 5.5 Hz; t, J = 3.8 Hz).Interpretation of the above data led us to assign 8a as the cis compound with nitrogen axial, and the lone pair electrons in a pseudo-axial position and antiperiplanar to the C7a and β-faced C2 protons.The amine 5a is also cis and has the nitrogen axial, but the lone pair electrons are pseudo-equatorial.Inspection of the Bohlmann band region in the ir of 5a and 8a supports the above assignments.These investigations thus suggest, in cis-octahydroindoles, the following steric order: methyl > lone pair > H.
