21271-06-7

Upstream product

• 51665-55-5 1-ethyl-6,7-dimethoxy-3,4-dihydroisoquinoline 
• 789477-69-6 1-(1'-methyl-2'-hydroxyethyl)-6,7-dimethoxy-3,4-dihydroisoquinoline 
• 112342-27-5 (6,7-dimethoxy-3,4-dihydro-2H-isoquinoline-1-ylidene)acetic acid ethyl ester 
• 21271-05-6 1-(1'-ethoxycarbonylethyl)-1,2,3,4-tetrahydroisoquinoline hydroiodide 

Downstream Products

• 142976-37-2 (1R,4S,4aS)-6,7-Dimethoxy-4-methyl-1-(4-nitro-phenyl)-4,4a,9,10-tetrahydro-3H-2-oxa-10a-aza-phenanthrene 
• 142976-35-0 (1S^*,11bR^*)-9,10-Dimethoxy-1-methyl-1,6,7,11b-tetrahydro-1H,4H<1,3>oxazino<4,3-a>isoquinoline 
• 142976-37-2 (1R,4R,4aS)-6,7-Dimethoxy-4-methyl-1-(4-nitro-phenyl)-4,4a,9,10-tetrahydro-3H-2-oxa-10a-aza-phenanthrene 
• 142976-35-0 (1R^*,11bR^*)-9,10-Dimethoxy-1-methyl-1,6,7,11b-tetrahydro-1H,4H<1,3>oxazino<4,3-a>isoquinoline 

Relevant academic research and scientific papers

Synthesis and stereochemistry of stereoisomeric 1,2,3-oxathiazino[4,3-a]isoquinolines

The ring-closures of homocalycotomine and its 1′- and 2′-methyl-substituted diastereomers 3, 4 and 7, 8 with thionyl chloride or with sulfuryl chloride led to 1,2,3-oxathiazino[4,3-a]isoquinoline derivatives 9-11 and 18, 19 or to 15, 17 and 22, 23, respectively. The relative configurations and the predominant conformations of the cis1-transcis2 conformational equilibrium were studied by means of 1H- and 13C-NMR spectroscopy, with the application of DNOE, 2D HSC and 2D-COSY measurements. In good agreement with the liquid-phase results, the X-ray investigations revealed that 9 and 10 have the cis1, while 18 has the trans-anellated stereostructure.

Synthesis and Conformational Study of 1,3,2-Oxazaphosphorino[4,3-a]isoquinolines: A New Ring System

A set of 1,3,2-oxazaphosphorino[4,3-a]isoquinolines 6a,b-9a,b, a new ring system, was synthesized, and their stereochemical and conformational analyses were performed by 1H, 13C, and 31P NMR methods. X-ray measurements were also carried out to confirm the stereochemical assignments and conformational results obtained by means of NMR. Intermediate coupling constants 3J(P,H) were found for compounds 7 and 9; these do not relate to equilibria between previously reported conformers, but are indicative of new distorted conformational states in solution. The connecting isoquinoline and the steric interaction between the aromatic moiety and the Me-1 substituent can block the oxazaphosphorinane ring. The conformational behavior of compounds 6 and 8 was characterized by the usual chair-twist equilibrium.

SATURATED HETEROCYCLES-113; SYNTHESIS AND STEREOCHEMICAL INVESTIGATION OF cis- AND trans-1-SUBSTITUTED 7,8-DIMETHOXY-1,4,5,9b-TETRAHYDRO-2H-AZETOISOQUINOLINES

Stereospecific and stereoselective syntheses starting from 1-- (1) and 1-ethoxycarbonylmethylene-6,7-dimethoxy-1,2,3,4-tetrahydroisoquinoline (13) gave cis- and trans-1-chloromethyl- (10, 4a), 1-methyl- (11, 12) and 1-benzyl-1,4,