Synthesis of a novel tetracyclic azaindolo[2,1-c][1,4]benzoxazine ring system

Tetrahedron Letters

Volumn 52, Issue 16, 2011, Pages 1874-1877

  Kurhade, Santosh ^a   Kaduskar, Rahul D ^a   Dave, Bhavesh ^a   Ramaiah, Parimi Atchuta ^b   Palle, Venkata P ^a   Bhuniya, Debnath ^a  

^a Advinus Therapeutics Private Limited Bangalore   (India)

^b ANDHRA UNIVERSITY   (India)

Author keywords

(N Boc) 2 amino 3 methylpyridine; 2 (2,4 Difluorophenoxy) 2,2 dimethylacetic acid; Azaindolo 2,1 c 1,4 benzoxazine; Diazaindolo 2,1 c 1,4 benzoxazine; Weinreb amide

Indexed keywords

AZAINDOLO[2,1 C][1,4]BENZOXAZINE; BENZOXAZINE DERIVATIVE; TRITERPENOID; UNCLASSIFIED DRUG;

ARTICLE; CONTROLLED STUDY; NONHUMAN; SYNTHESIS;

PUFFINUS AURICULARIS;

EID: 79952737944     PISSN: 00404039     EISSN: None     Source Type: Journal    
DOI: 10.1016/j.tetlet.2011.02.020     Document Type: Article

References (22)

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13. 3 solution. The organic mass was extracted with ethyl acetate (20 mL x 3). The combined organic layer was given a brine wash (50 mL), dried over anhydrous sodium sulfate, and finally concentrated on rotavapour to afford the crude product, which was then purified by silica-gel column chromatography (60-120 mesh, eluents: hexanes to 30% ethyl acetate in hexanes) to obtain analytically pure 3a (406 mg, 70%) along with minor amount of 2-(propen-2-yl)-7-azaindole 4a (70 mg, 24%).
14. In addition to Ref. 5, the below literature was consulted to come up with the typical procedure described here in Ref. 6: Caulkett, P. W. R.; Mckerrecher, D.; Newcombe, N. J.; Pike, K. G.; Robb, G. R.; Waring, M. J. in PCT Publication No. WO 2007/031739 A1.
15. +: 269.1090, found: 269.1086.
16. 6): δ 20.50, 99.03, 113.05, 116.07, 120.92, 128.36, 134.70, 139.69, 143.56, 149.96. HPLC purity: 99%. LC-MS (m/z): 159.1 [M+1] base peak.
17. +: 387.1720, found: 387.1722.
18. +: 389.1876, found: 389.1876.
19. 3): δ 27.04 (2C), 75.82, 96.02, 100.38 (dd, J = 27.1, 21.6 Hz), 101.89 (dd, J = 28.6, 3.0 Hz), 118.02, 122.17, 128.12 (dd, J = 14, 5.4 Hz), 128.30, 129.46 (m, 1C), 139.15, 143.87, 147.84, 152.54 (dd, J = 244.6, 13.9 Hz), 156.79 (dd, J = 238.5, 12.4 Hz). HPLC purity: 99%. LC-MS (m/z): 287.2 [M+1]. Structure of 3d was further confirmed using single crystal X-ray analysis (CCDC-785444; www.ccdc.cam.ac.uk). The ORTEP view is shown here: (Chemical Equation Presented)
20. +: 309.1403, found: 309.1417.
21. +: 199.1235, found: 199.1228.
22. +: 269.1090, found: 269.1079.