N⁴‐Benzoylspermidine from Oncinotis tenuiloba: Analytical differentiation of the three isomeric N‐benzoylspermidines

Abstract

During the examination of extracts from Oncinotis tenuilobu STAPF a new polyamine, N4-benzoylspermidine (S), was isolated. For unambiguous structure elucidation, it was transformed into the diacetyl derivative 13, and the three possible N-benzoyl-substituted isomers of spermidine 5 , 8 , and 11 together with their peracetylated derivatives 12-14, respectively, were synthesized and identified.

Selective Synthesis of Polyamine Derivatives: Efficient derivatization of the secondary amino group of N‐monosubstituted 1,3‐diamines

“…By the action of day-light, the C=C bonds of the 3-phenylprop-2-enoyl moieties can isomerize [26], giving rise to even more isomeric species. Similar effects as with 4 a and 15 were observed with internally and terminally acylated spermidine [27] [28].…”

Structure, Biological Activity and Synthesis of Polyamine Analogues and Conjugates

“…[35] These units can be either the same or combinations of HCA units. [36] Recently, N 4 -benzoylspermidine [37] and tenuilobine (14) [38] were isolated from the same source. Compound 14 is the first PA alkaloid containing both SPM and SPD, cross-conjugated through a long aliphatic chain.…”

Synthetic Analogues to the Spermidine-Spermine Alkaloid Tenuilobine

“…C); 135.3 (s, C(1), C(3)); 129.5, 129.3, 129.2 (3d, 5 arom. C); 129.1 (d, C(4), C(6)); 76.6 (t, PhCH 2 ); 36.8 (t, C(2'')); 35.6 (t, 2 C(2')); 31.5 (t, C(3'')); 26 [21] [22] (1.48 g, 3.6 mmol) in CH 2 Cl 2 (18 ml), the mixture was stirred overnight at r.t. The solvent was evaporated, the residue was taken up in CH 2 Cl 2 (150 ml), washed with 0.3n aq.…”

“…To confirm the isomerization of 12, 15 was synthesized according to the Mukaiyamas method of amide formation. Thus, 7 was treated with the spermidine derivative 17 [26] in the presence of 1-methyl-2-chloropyridinium iodide, to give the fully protected amide 18 in 30% yield. Deprotection of the Bn group of 18 by hydrogenolysis (H 2 /Pd/C), followed by removal of the Boc groups with CF 3 COOH, yielded 15, which, on the basis of spectroscopic data, was found to be identical to the compound obtained by isomerization of 12 (Scheme 5).…”