Among the isoprenylated dehydrotryptophan derivatives isolated from the mycelium of Aspergillus amstelodami, two optically inactive compounds previously referred to as cryptoechinuline B and D were interesting due to their apparent molecular complexity. We now report spectral evidence allowing the assignment of structures (2) and (1) to these compounds, respectively. (i) The ¹H NMR spectrum of (1) [270 MHz, 0.05 M, (CD₃)₂SO] showed 41 hydrogen atoms, consistent with the C₂₇H₃₁N₃O₃ molecular composition determined by exact mass measurements. Five protons (δ 11.8, 10.9, 9.2, 8.8, and 7.8) were exchanged upon addition of 5% D₂O. (ii) The ¹H signals at δ 8.8 and 7.8 suggested two CONH groups, consistent with two CO absorptions in the ¹³C NMR spectrum [22.6 MHz, 0.3 M, (CD₃)₂SO] at δ 161.5 and 167.8 ppm. The ¹H signal at δ 10.9 was in the range expected for tryptophan NH, and aromatic ¹H signals between δ 6.9 and 7.5 formed a 4-spin pattern typical of the tryptophan benzene ring. A system of 3 protons at δ 1.4 and a ¹³C singlet at δ 38.6 ppm suggested an αα-dimethylallyl chain at position 2 of tryptophan, as in the echinuline series. The ¹H absorption at δ 6.97 (3a-H) and ¹³C absorptions at δ 144.4 ppm (C-3b) and 111.7 ppm (C-3a), together with other data, indicated a dehydrotryptophanyl residue linked to another amino acid residue to form a diketopiperazine ring, as in the neoechinuline series. (iii) For remaining proton signals, analysis of the pattern assigned to fragment (3) was done via double resonance experiments (decoupling and INDOR, starting from 7'-H at δ 6.7) and chemical shift/coupling constant considerations. (iv) A γγ-dimethylallyl chain was deduced from the -CH₂CH= proton pattern (δ 3.2 and 5.2) and diagnostic methyl resonances in both ¹³C (δ 17.7 and 25.6 ppm) and ¹H (δ 1.6) spectra. (v) A ¹³C signal at δ 197.3 ppm with a doublet structure (coupling to δ 10.2) indicated a CHO group. (vi) A ¹³C singlet at δ 59.2 ppm showed a quaternary carbon with a deshielding substituent. (vii) Comparing fragment carbon atoms (32) with the molecular formula and full ¹³C spectrum (38) revealed six additional unsaturated carbons in (1), giving 15 unsaturations and 5 rings (via formula (2C + N - H + 2)/2 - 15). With two rings in tryptophan and one in diketopiperazine, the rest of the molecule had two rings, rationalized as a penta-substituted benzene linked to fragment (3) (forming a cyclohexene ring with the δ 59.2 ppm quaternary carbon). Aromatic substituents included γγ-dimethylallyl, CHO, and phenolic OH (shown by exchangeable protons at δ 9.2/11.8 and ipso carbons at δ 147.1/153.1 ppm); the only ring-attached hydrogen was a singlet at δ 7.02. The aromatic substitution pattern was unresolved by these results. (viii) The ¹H spectrum of (2) (C₃₂H₃₇N₃O₅, exact mass) resembled (1) but added two Me resonances (δ 1.7) and a -CH₂CH= pattern (δ 3.3 and 5.3). The tryptophan aromatic absorption was an ABX system (similar to neoechinuline C), indicating a γγ-dimethylallyl chain at position 6. (ix) The molecular framework suggested derivation from auroglaucine and neoechinuline B/C via regiospecific Diels-Alder condensation (terminal diene of auroglaucine with dehydroalanine units of neoechinulines). Heating auroglaucine with neoechinuline B/C at 150 °C overnight gave crude mixtures from which products identical to (1)/(2) (mixed m.p., chromatography, mass spectra) were isolated via SO₂ chromatography, confirming the aromatic substitution pattern. The compounds likely arise from natural dehydroamino-acid derivatives during fungal mat extraction, representing a new feature of this important natural product class.