Re-examination of the basic material obtained by extracting the leaves of Temnletonia retusa led to the isolation of (-)-cytisine, (-)-anagyrine, (+)-lupanine, a trace of (±)-piptanthine, and a new alkaloid (-)-templetine (C₂₀H₃₅N₃) which crystallized from acetone as prisms (m.p. 120.5-122.0 °C, [α]ᴅ-58° in ethanol). Reactions with methyl iodide, formaldehyde, and carbon disulphide revealed it contained one tertiary and two secondary nitrogen atoms; its failure to undergo catalytic hydrogenation suggested it belonged to the C₂₀ Ormosia alkaloids, confirmed by dehydrogenation with 10% Pd/C to (-)-dehydropiptanthine (identified by comparing its perchlorate with the enantiomer (+)-dehydropiptanthine—obtained from (-)-ormosanine dehydrogenation—via TLC, IR, UV, NMR, and mass spectroscopy). Infrared spectrum (CCl₄) showed Bohlmann bands at 2800, 2770, 2730, and 2655 cm⁻¹ indicating a m-quinolizidine moiety; mild dehydrogenation with mercuric acetate gave a monodehydro derivative (characterized as sulphate, m.p. 221-222 °C) that catalytically reduced back to (-)-templetine. Since chemical and spectroscopic methods couldn't define remaining asymmetric centers, X-ray crystallographic analysis of (-)-templetine trihydrochloride dihydrate was undertaken: crystals are orthorhombic (space group P2₁2₁2₁, a=8.83(4) Å, b=14.201(6) Å, c=19.122(12) Å, Z=4, dcalc=1.282 g cm⁻³). Intensity data were collected to 2θmax=132° (corrected for absorption), structure solved via the MULTAR program, and absolute configuration determined by the lower R factor (0.101 vs 0.106 for the two enantiomers). Final refinement (all atoms anisotropic except H, which were isotropic) gave R=0.045, leading to its conformation and absolute configuration. Degradative work relating (-)-templetine to (-)-ormosanine and (-)-panamine via enantiomeric dehydropiptanthines enabled assignment of absolute structures to (-)-ormosanine and (-)-panamine; epimerization of (-)-templetine at C6 yielded a more stable isomer enantiomeric with (-)-piptanthine from Piptanthus Hance.