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US3576887A Expired / Lapsed US ⏱️ 0.0 years remaining

Process for the preparation of oxaphenanthrenes and intermediates therefor

Assignee: Wyeth LLC
•
Filing: 1967-05-01
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Granted: 1971-04-27
•
Expires: 1987-05-01
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Abstract

Abstract 6,6-DIALKYLTETRA-HYDRO- AND HEXAHYDRO-6H-DIBENZO (B,D) PYRANS (I) ARE OBTAINED BY CYCLODEHYDRATING A 1-(1''-HYDROXY)ALKYL-2-O-HYDROXYPHENYLCYCLOHEXANE OR -ONE (III). COMPOUNDS (III) ARE OBTAINED BY TREATING A 2-O-ALKOXY-PHENYLCYCLOHEXANE- OR ENECARBOXYLIC ACID OR ESTER (II) WITH A GRIGNARD REAGENT. ENANTIOMORPHIC COMPOUNDS (I), PARTICULARLY, (-) -$8-TETRAHYDROCANNABINOL, A BIOLOGICALLY ACTIVE, ASYMMETRIC CONSTITUENT OF HASHISH, ARE PREPARED BY CYCLIZING THE CORRESPONDING ENANTIOMORPHIC COMPOUNDS (III).

Inventors

  • 👤 Gordon A Hughes
  • 👤 Timothy Y Jen
  • 👤 Herchel Smith

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-11-03 17:39
CPC Classifications
C; C07; C07C; C07C39/00; C07C39/23; C07D; C07D311/00; C07D311/02; C07D311/78; C07D311/80; C07C2601/00; C07C2601/12; C07C2601/16

Claims Analysis

Total Claims: 0
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References Cited (Backward Citations)

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USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1974-04-26 1974-10-26 1975-04-27 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1978-04-26 1978-10-26 1979-04-27 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1982-04-26 1982-10-26 1983-04-27 $7700.00 Window Closed / Lapsed

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