The X-Ray Crystal-Structure of (+/-)-Pandamarine, the Major Alkaloid of Pandanus-Amaryllifolius

Abstract

The structure (2) of ( �)-pandamarine , the major alkaloid isolated from the leaves of Pandanus amaryllifolius Roxb., has been determined by an X-ray diffraction study. Diffractometer data at 295 K were refined by least-squares techniques to a residual of 0.049 2244 'observed' reflections). Crystals of (2) are triclinic, P1, a 13.077(2), b 9.857(5), c 7.214(2) �, α 106.91(3), β 96.22(2), γ 100.01(2)0, Z 2.

First Total Synthesis of Pandamarine

“…2 Biogenetically, the isolation team have proposed that pandamarine (1) might be the spiro-N,N-ketalization product of a symmetric bis-lactam (3, Scheme 1). 1,3 This proposal is consistent with the fact that pandamarine (1) occurs as a racemate. It was suggested that this possible biogenetic intermediate 3 might in turn be obtained from (2S)-4-hydroxy-4-methylglutamic acid (4, Scheme 1) since this amino acid was found in a related species, P. veitchii.…”

“…Pandamarine (1, Scheme 1) is an alkaloid that was isolated in 1992 by Byrne's group from the leaves of the tropical plant Pandanus amaryllifolius. 1 Pandamarilactone-1 (2, Scheme 1), was also isolated from the same plant one year later. 2 Biogenetically, the isolation team have proposed that pandamarine (1) might be the spiro-N,N-ketalization product of a symmetric bis-lactam (3, Scheme 1).…”

“…Pandamarine's structure was determined by X-ray diffraction 1 and consists of both a diazaspiro[4.5] and a 5ylidenepyrrol-2(5H)-one unit, connected by a carbon chain (C7-C9, 1, Scheme 1). The diazaspiro [4.5] motif is found in a small number of other natural products such as: haplophytine, 8 isoschizogamine 9 and the related alkaloids leuconoxine, 10 the leuconodines 11 and melodinine E. 12 In contrast, the 5ylidenepyrrol-2(5H)-one unit is ubiquitous appearing in many natural products and pharmaceuticals.…”

“…The 1 H and 13 C NMR data are in full agreement with those reported in the isolation paper. 1 In order to find out if lactam 3 was indeed the precursor of the natural product (1), under the conditions we had employed, Scheme 5. Synthesis of Pandamarine from Difuran 7 compound 3 was prepared independently starting from the Boc-protected di(furylalkyl)amine 13 (Scheme 6).…”

A divergent asymmetric approach to aza-spiropyran derivative and (1S,8aR)-1-hydroxyindolizidine

“…[ 1 - 3 ] The corresponding aza-spiroketal (cf: general structure B ) containing natural products, while less common, are also found in plants, shellfish and microbes. [ 4 , 5 ] For example, pandamarilactone-1 and pandamarine were isolated from the leaves of Pandanus amaryllifolius ;[ 6 ] solasodine and its derivatives were isolated from Solanum umbelliferum , which exhibited significant activity toward DNA repair-deficient yeast mutants;[ 7 ] azaspiracids are marine phycotoxins isolated from cultivated mussels in Killary harbor, Ireland;[ 8 ] and chlorofusin A is a novel fungal metabolite showing the potential as a lead in cancer therapy. [ 9 ] In addition, aza-spiropyrans C , being able to equilibrate with the corresponding non-spiro analogue D , is a well known class of compounds possessing photochromic properties for use in the area of photochemical erasable memory,[ 10 ] and also found applications as self-development photography, actinometry, displays, filters, lenses of variable optical density,[ 11 ] and photomechanical biomaterials etc.…”