J . Org. C h e m . , Vol. 44 &'a 25, I979 4709
Notes for the HA-100 spectra, Barbara B. Morgan for the CFT-20 spectra, and Timothy E. Hof for technical assistance. Registry No. crs-l,71870-63-8; trans-1, 71870-64-9;2, 71870-65-0 ethyl acetoacetate, 141-97-9;styrene oxide, 96-09-3.
U v a r i n o l : A Novel Cytotoxic T r i b e n z y l a t e d F l a v a n o n e from Uvaria chamae Charles D Hufford and Wiiliam 1, Lasswell, Jr Departrner t or Pkarrnacognosj, School of Pharmac), I'niLersctx o; Vitrlssrppi I'nzcersitj, Mississippi 38677
Ken Ilirotsu and Jon Clardy*
Figure 1. A perspective drawing of the ?(.ray model of uvarinol
Baker Laboratori D e p a r t m e n t of Chernistr3, Cornel1 I'riiverszt3, Ithaca, Nru, York 14853
(1). Hydrogens are omitted for clarity. and the absolute configuration was deduced from CD data.
'H NMR spectrum (60 MHz, acetone-d,) clearly showed an ABX pattern characteristic of the protons a t C-3 (6 2.70-3.00, AB) and C-2 (6 5.70, dd. X ) of a flavanone. A Recently w(li and others? have isolated cytotoxic com1 H singlet a t 6 13.30 (OH a t C-5, exchanges with DzO), pounds from plants of t h e C'uaria genus. We now wish three 2 H singlets a t 6 4-00, 3.97, arid 3.87 (ArCH,Ar), to report t h e j t r u c t l r e of uvarinol ( l ) ,the most complex sixteen aromatic protons between 6 6.60 and 7.90, and four yo 4 \ additional exchangeable protons comprised the rest of the ( 7 spectrum. T h e absence of an upfield aromatic proton drogen bonds could pg/mL and against PS cell cultures a t 9.7 pg/mL as well play an important role in determininq the molecular conas significant antimicrobial activity against Staphylococcus formation. Molecules related bj- a c.axis translation are aui-eus, Racilius s d ) f i l i s ,and Mycobacterium smegmut1s.j linked by two intermolecular hydrogen bonds: O(32)H. A molecular formula of C36H300-was established by ..0(24) a n d 0(41)H-.0(1.5). Surprisingly unly van der high-resolution mass spectroscopy and combustion analWaals interactions are found between symmetry-indeysis. T h e UV (A,, (MeOH) 329 nm ( t 16000)) and IR pendent molecules. spectra ( K B r , J100 (broad, OH), 1628 cm (0)) were Uvarinol (1) is thus a tribenzylated flavanone. T h e consistent with a dihydroxylated flavanone nucleus. lq2 The flavanones are of course widespread tn the higher plants, but the addition of benzyl groups is quite rare and seems l___l_____._..." -__ to be limited to U ~ a r i a . ' - ~The b e n q l groups presumably (11 C. I). Huffrird aiicl W. L. Lasswell, Jr., J . Org. C'htm.. 41. 1297 arise from a C&, pathway, but the o-hydroxy function119%). ( 2 ) W ,L. Lasswell, ! r , and C. D. Hufford, J . Org. Chern., 42, 1295 ality is unusual. Recently a biogenetic scheme that would (19771. generate o-hl droxybenzyl groups from isochorismate has ( 3 ) J . R. Cole, 5. J. Torrance, R.M.Weidhopf. S. K . Arora. and R. H. been suggested.8 Rates,
