The amaryllidaceae alkaloids

Lycorine, the Main Phenanthridine Amaryllidaceae Alkaloid, Exhibits Significant Antitumor Activity in Cancer Cells That Display Resistance to Proapoptotic Stimuli: An Investigation of Structure−Activity Relationship and Mechanistic Insight

“…53 The compound was generously supplied by Prof. H. M. Fales, Department of Health Education and Welfare, Bethesda, MD, USA. The 1 H NMR spectrum (400 MHz, CDCl 3 -CD 3 COOD, 3:1 v/v) differed from that of the lycorine for the presence of the singlet at δ 7.90 due to the N -methyl.…”

“…5,53 1 H NMR (400 MHz, CDCl 3 ): δ 6.79 (s, H-12), 6.56 (s, H-8), 5.93 (d, J = 1.5 Hz, H-11A) 5.90 (d, J = 1.5 Hz, H-11b), 5.45 (m, H-3), 5.01 (m, H-2), 4.64 (dd, J =2.2 and 2.0 Hz, H-1), 4.12 and 3.52 (1H each, d, J = 14.0 Hz, H 2 -7), 3.36 and 2.40 (1H each, m, H 2 -5), 3.11 (dd, J = 10.7, 2.0 Hz, H-12b), 2.82 (d, J = 10.7, H-12c), 2.63 (m, H 2 -4). [α] 25 D -194.4 ( c 0.1, CHCl 3 ); UV (EtOH) nm (log ε): 290 (3.74), 235 (sh); IR (CHCl 3 ) 1620, 1505, 1485 cm -1 ; EI MS, m/z : 269 [M] + , 265, 250, 227, 226.…”

Nonbasic Aporphine Alkaloids from Liriodendron Tulipifera L

“…The 60-MHz NMR spectrum (CDC13) showed three 3H singlets at 6 2.17 (-NCOCH3), 3.60, and 3.82 (-OCH3), a 2H singlet at 6 5.85 (-OCH,O-), and three 1H singlets at 6 6.48, 6.62, and 7.82 (Ar-H). It exhibited a parent ion peak at mle 367.1390 corresponding to the formula C21H21N05 (calculated mle 367.1420), which was also supported by elemental analysis.…”

“…In continuing investigations on peyote and related alkaloids (6,7), the authors extended the work to the study of I and its methylenedioxy analog (11). The synthesis of racemates of I and I1 is reported here Vol.…”

Asymmetric Total Syntheses of (−)‐α‐Lycorane, (−)‐Zephyranthine, and Formal Synthesis of (+)‐Clivonine

“…At an early stage of exploring this class of alkaloids, transformations connecting the different members were investigated. In this context, natural products containing the tetracyclic core structure such as a-lycorane (2), [3] zephyranthine (3), [4] lycorine (6), [5] dihydrolycorine (7), [5a] and a-dihydrocaranine( 8) [4c, 6] could all be derived from intermediate 1.T he carbon-carbon double bond in ring Co fi ntermediate 1 playeda ni mportant role in the divergents yntheses of these natural alkaloids. Previously, intermediate 1 was either synthesizedi nr acemic form [4c, 5a] or derived from the optically pure natural product,( À)-lycorine (6).…”