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Methanol extraction of the ground seeds of Uncaria Gambier Roxb. followed by chromatography afforded a crystalline C30H38O10 terpene. This has been shown by X-ray analysis to be 7α-acetoxydihydronomilin. The crystals are orthorhombic, P212121, a = 13.158(2), b = 17.092(2), c = 12.689(2) Å, Z = 4, dx = 1.300, do = 1.300 g cm−3. The structure has been determined by the direct method and Fourier syntheses, and refined by block-diagonal least-squares to R = 0.042 for 2621 observed reflexions. The molecule contains a seven-membered lactone ring A, three six-membered rings B, C, D, a three-membered ring E, a furan ring F, and two acetate groups. A and B are chair, C is twist-boat, D is 1,3-diplanar, while E and F are planar. The A/B, A/C, C/D junctions are trans, D/E is cis, and F is linked to D by an equatorial C—C bond. The two acetate groups are in axial positions on A and B and are cis to each other. The O atom forming the apex of the three-membered ring is wedged between two H atoms and their parent C atoms at short intramolecular distances O … H = 2.28(2) and 2.28(3), and O … C = 2.623(3) and 2.668(4) Å. No intermolecular hydrogen bonding is indicated.

A side product accompanying the reaction of N-methoxycarbonyl-L-valine anhydride with an amino acid anion in aqueous dimethylformamide has been characterized by an X-ray analysis as N,N′-bismethoxycarbonyl-L-valyl-L-valine, C14H24N2O7. The crystals are orthorhombic, space group P212121, a = 14.581(2), b = 17.110(2), c = 6.970(1) Å, Z = 4. The structure was determined by the direct method, and refined by block-diagonal least squares to R = 0.046, Rw = 0.053 for 1759 reflections with I ≥ 3σ(i). The carboxy-terminal part of the dimer is in the gauche conformation while the other part is trans. Each molecule at (x, y, z) makes two hydrogen bonds O … H—O and N—H … O to the molecule at (1 − x, y − 1/2, 1/2 − z) and similarly to that at (1 − x, 1/2 + y, 1/2 − z) to form infinite ribbons along y.

The synthesis of 5-allyl-2'-methoxy-9-oxo-6,7-benzomorphan (5b) is described. The 10-hydroxy-2-methyl-1,11-propano-9H-indeno-1,2,10,11-tetrahydro[2,1-c]pyridine (7a) and the corresponding 6-methoxy derivative (7b) are unexpected products of pyrolysis of 5-allyl-2-methyl-9-oxobenzomorphan methobromide (4a) and 5-allyl-2′-methoxy-2-methyl-9-oxobenzomorphan methobromide (4b) respectively. The molecular structure of 7a (C16H19NO) has been determined from spectral and microanalytical data, and confirmed by X-ray single crystal analysis on its hydrobromide salt using the heavy atom technique. The crystals of [C16H20NO]+Br− are monoclinic, P21/a, with a = 13.724(2), b = 14.022(3), c = 7.495(2) Å, β = 97.33(5)°, and Z = 4. The crystal structure has been refined by block-diagonal least-squares calculations to R and Rw = 0.036 for the 2197 observed reflections. The N atom has planar trigonal coordination, and forms one double and two single C—N bonds of lengths 1.273(4), 1.465(4), and 1.474(4) Å, respectively. The Br is hydrogen-bonded to O. The N and O atoms are trans.