Isolation of glucosinolates and the identification of o-(α-l-rhamnopyranosyloxy)benzylglucosinolate from Reseda odorata

A method has been developed for the quantitative isolation of glucosinolates by ion-exchange chromatography and high voltage electrophoresis avoiding strongly alkaline and acidic conditions. The compounds were identified by ¹H and ¹³C NMR spectroscopy and through the products arising from enzymatic, acid and alkaline hydrolysis. The method is well suited for the isolation and identification of glucosinolates containing aglucone parts which produce non-volatile compounds on enzymatic hydrolysis. The method has been used in the isolation and identification of 2-hydroxy-2-methylpropylglucosinolate from Reseda alba, 2-hydroxy-2-phenylethylglucosinolate from R. luteola and a new glucosinolate, o-(α-l-rhamnopyranosyloxy)benzylglucosinolate, occurring in R. odorata. The glucosinolate content in different parts of this plant has been determined and the metabolism of glucosinolates is briefly discussed.     

Eudistomidin G,a new β-carboline alkaloid from the Okinawan marine tunicate Eudistoma glaucus and structure revision of eudistomidin B

A new β-carboline alkaloid, eudistomidin G (1), has been isolated from the Okinawan marine tunicate Eudistoma glaucus, and the structure was elucidated from spectroscopic data. Furthermore, the structure of eudistomidin B (2), which has been isolated from the same tunicate, was revised from 2a to 2b by detailed analyses of spectroscopic data. Asymmetric synthesis of the revised structure (2b) of eudistomidin B (2) and its (1S,10S)-diastereomer (2c) has been accomplished with the Noyori catalytic asymmetric hydrogen-transfer reaction. The absolute configuration of eudistomidin B (2) was confirmed to be 2b possessing (1R,10S)-configuration, from comparison of the ¹H NMR data, CD spectra, [α]_D values, and HPLC analysis of 2b, 2c, and natural eudistomidin B.     

Chromosomal variation and evolution in Lycoris (Amaryllidaceae) I. Intraspecific variation in the karyotype of Lycoris chinensis Traub

In 188 bulbs from five populations of Lycoris chinensis from Anhui province, China, several chromosomal variations have been discovered. Although their frequencies are low, some rearranged chromosomes which are aberrant have been found. The aberrants are: (1) small metacentrics (m′); (2) submetacentrics (sm); (3) subtelocentrics (st); (4) acrocentrics (t); and (5) satellite chromosomes (SAT). All can be easily suspected as being derived from telocentric chromosomes (T type chromosomes). Some individuals having one or more B chromosomes have been found, and intrapopulational variation of B chromosomes in number has also been observed. Because of having B chromosome, L. chinensis has some different chromosome complement numbers: 2n?=?16, 2n?=?16?+?1B, 2n?=?16?+?2B, 2n?=?16?+?3B, and 2n?=?16?+?5B. In addition, a new triploid karyotype composed of 3n?=?24?=?9m?+?11t(2SAT)?+?4T chromosomes has been found. Vegetative propagation is an efficient means of perpetuating the aberrant chromosomes and the triploids.     

Sesquiterpenoid metabolites from Stereum complicatum

A new sesquiterpene antibiotic, complicatic acid, isolated from cultures of Stereum complicatum (Fr.)Fr. has been shown to be dehydrohirsutic acid C. Hirsutic acid C was also isolated from the same fungus. [2-¹⁴C]-MVA was incorporated into both metabolites and complicatic acid has been shown to be formed from hirsutic acid C both in vivo and in vitro.     

Purification and characterization of myo-inositol hexaphosphate-adenosine diphosphate phosphotransferase from Phaseolus aureus

myo-Inositol hexaphosphate adenosine diphosphate phosphotransferase transfers phosphate from myo-inositol hexaphosphate to adenosine diphosphate to synthesize adenosine triphosphate. This enzyme has been isolated and purified from ungerminated mungbean seeds and found to be different from guanosine diphosphate phosphotransferase. A purification of about 200-fold with 15% recovery has been obtained. The optimal pH of the reaction is 7.0 and is dependent on the presence of a divalent cation, i.e., Mg²⁺ and Mn²⁺. The K_m value for myo-inositol hexaphosphate has been found to be 0.41 × 10^?4m and V is 90.0 nmol of P_i transferred per milligram of protein per 20 min. K_m for ADP is 0.88 × 10^-4m and V is 83.3 nmol of phosphorus transferred to ADP per milligram of protein per 20 min. The ADP phosphotransferase reaction is reversible to the extent of about 50% of the forward reaction. dADP is partly effective as an acceptor but other ribonucleoside mono- and diphosphates cannot substitute for ADP. The products ATP and myo-inositol pentaphosphate have been confirmed by several criteria. It has also been shown that this enzyme transfers phosphate only from a specific phosphoryl group (C-2 position) of myo-inositol hexaphosphate for the synthesis of ATP and 1,3,4,5,6-myo-inositol pentaphosphate or pentakis (dihydrogen phosphate).     

The synthesis of some methy 4,6-O-Benzylidene-α-D-erythro-Hexopyranosid-2,3-Diulose derivatives

Methyl 4,6-O-benzylidene-3-deoxy-3-phenylazo-α-D-glucopyranoside (1) has been oxidised with the Pfitzner—Moffat reagent to the 2,3-diulose 3-phenylhydrazone derivative (2) which has been characterised as the phenylosazone (3) and oxime (4). An unstable 2-imino derivative (10) of the same diulose has been produced by base-catalysed elimination of nitrogen from methyl 2-azido-4,6-O-benzylidene-2-deoxy-α-D-ribo-hexopyranosid-3-ulose (8). The imino intermediate was trapped as a quinoxaline derivative (9). The base-catalysed reactions of certain other hydrazone derivatives of methyl hexosiduloses have also been examined.     

Isopentenyladenine from mutants of the moss, Physcomitrella patens

The culture media from gametophore over-producing mutants of the moss Physcomitrella patens have been examined for their cytokinin content. Two cytokinins have been detected, one of which has been identified as N⁶-(Δ²-isopentenyl) adenine (2iP).     

(—)-Massoniresinol,a lignan from Pinus massoniana

A new lignan, named (—)-massoniresinol, has been isolated from Pinus massoniana needles. Its structure has been proved to be (2R,3S,4R)-3,4-dihydroxy-2-(4-hydroxy-3-methoxyphenyl)-4-(4-hydroxy-3-methoxybenzyl)-3-tetrahydrofuranmethanol by ¹H NMR, ¹³C NMR, mass and CD spectroscopy.     

Isolation and structure of wallichoside,a novel pteroside from Pteris wallichiana

Wallichoside has been isolated from the rhizomes of Pteris wallichiana and its structure and absolute configuration has been established as the 3-β-d-glucoside of 2S, 3S-pterosin C on the basis of UV, IR, NMR and MS data of wallichoside and its derivatives.     

Antifungal cinnamic acid derivatives from Persian leek (Allium ampeloprasum Subsp. Persicum)

A cinnamic imidate, (1Z,2E)-methyl 3-(-p-hydroxy-m-methoxyphenyl)-N-(-p-hydroxyphenethyl) acrylimidate, named persicoimidate (1), has been isolated and characterized from bulbs and seeds of Persian leek, Allium ampeloprasum Subsp. Persicum. Two cinnamic acid derivatives, N-feruloyl tyramine (2) and N-caffeoyl tyramine (3) were isolated from bulbs and seeds. Compound 2 has been previously reported from garlic and leek, while compound 3 is described in Allium plants for the first time. The chemical structures of the isolated compounds have been elucidated unambiguously by spectroscopic methods, including 2D NMR and MS. The isolated compounds were evaluated for their antifungal activity against four fungal pathogens, the soil-borne pathogen Penicillium italicum, the air-borne pathogens Aspergillus niger and Botrytis cinerea, and the antagonistic fungi Trichoderma harzianum to evaluate the possible involvement of such compounds in resistance to pathogen attack.     

Lignans and aporphine alkaloids in bark of Liriodendron tulipifera

Lirionol, a novel tetracyclic lignan, has been isolated from the bark of Liriodendron tulipifera and its structure determined by spectroscopic analysis. In addition, syringic acid methyl ester, (+)-pinoresinol, (+)-syringaresinol, N-(2-hydroxy-2-phenylethyl)benzamide and O-methyl-N-norlirinine have also been isolated. The structures of lirinine and related compounds isolated from the leaves of this tree-species by Yunusov et al. are also discussed.     

Cytokinins in Corynebacterium fascians Cultures: Isolation and Identification of 6-(4-Hydroxy-3-methyl-cis-2-butenylamino)-2-methylthiopurine

In addition to the four cytokinins, 6-(3-methyl-2-butenylamino)purine, 6-methylaminopurine and the cis and trans isomers of 6-(4-hydroxy-3-methyl-2-butenylamino)purine, reported earlier from our laboratories, three cytokinin-active fractions have been obtained from the aqueous medium of 6-day-old Corynebacterium fascians cultures. One of these has been identified as 6-(4-hydroxy-3-methyl-cis-2-butenylamino)-2-methylthiopurine (2-methylthio-cis-zeatin, c-ms²io⁶ Ade).     

Generation of primary amide glucosides from cyanogenic glucosides

The cyanogenic glucoside-related compound prunasinamide, (2R)-β-d-glucopyranosyloxyacetamide, has been detected in dried, but not in fresh leaves of the prunasin-containing species Olinia ventosa, Prunus laurocerasus, Pteridium aquilinium and Holocalyx balansae. Experiments with leaves of O. ventosa indicated a connection between amide generation and an excessive production of reactive oxygen species. In vitro, the Radziszewski reaction with H₂O₂ has been performed to yield high amounts of prunasinamide from prunasin. This reaction is suggested to produce primary amides from cyanogenic glycosides in drying and decaying leaves. Two different benzoic acid esters which may be connected to prunasin metabolism were isolated and identified as the main constituents of chlorotic leaves from O. ventosa and P. laurocerasus.     

Alkaloids of Litsaea laeta and L. salicifolia

The structure for laetine (2-hydroxy-1-methyl 10,11-methylenedioxy noraporphine), a new alkaloid from the bark of Litsaea laeta has been established. N,O-Dimethylharnovine and glaucine were also isolated from the same source. C-2 hydroxy aporphines are characteristic of L. laeta. Two known alkaloids, dicentrinone and nordicentrine, have also been isolated from the leaves of L. salicifolia.     

Structure of a cyanoglucoside of Lithospermum purpureo-caeruleum

A new glucoside has been isolated from roots of Lithospermum officinale and L. caeruleum. It is not cyanogenetic although containing nitrile group in the aglycone moiety. Its structure has been elucidated by ¹H and ¹³C NMR spectroscopy as 6-O-β-d-glucopyranosyl-1-cyanomethylene-4, 5-dihydroxy-2-cyclohexene.     

Saccharopine and 2-aminoadipic acid in Reseda odorata

2(S),2′(S)-N⁶-(2′-Glutaryl)lysine (l-saccharopine) and 2(S)-2-aminoadipic acid have been isolated from Reseda odorata. When traditional isolation procedures are used l-pyrosaccharopine (5(S),5′(S)-N-(5′-amino-5′-carboxy-pentyl)-2-pyrrolidone-5-carboxylic acid) is formed from l-saccharopine by lactamisation. The degree of lactamisation during various isolation steps has been studied, The amino acids were identified by IR and PMR spectroscopy and the configurations established by enzymic and polarimetric analyses. The contents of saccharopine and 2-amino-adipic acid have been determined relative to the total nitrogen content at various stages in the growth cycle of R. odorata.     

Part 3: Design and synthesis of proline-derived α2δ ligands

A potent series of substituted (2S,4S)-benzylproline α₂δ ligands have been designed from the readily available starting material (2S,4R)-hydroxy-l-proline. The ligands have improved pharmacokinetic profile over the (4S)-phenoxyproline derivatives described previously and have potential for development as oral agents for the treatment of neuropathic pain. Compound 16 has been progressed to clinical development.     

Leaf wax constituents of some myrtaceous species

Eucalyptin and 8-desmethyleucalyptin have been isolated from the leaf wax coatings of several species of Eucalyptus, from Syncarpia glomulifera, Lophostemon confertus and an Angophora hybrid indicating that C-methylated flavones may be fairly distinctive of the family Myrtaceae. Ursolic acid has been isolated from the leaf waxes of E. youmanii, S. glomulifera, Leptospermum petersonii and Melaleuca quinquenervia, friedelin from Lophostemon confertus and 4,6-dimethoxy-2-hydroxyacetophenone from E. michaeliana.     

Larch chromosomal mosaicism

Karyological study of larch population members from different parts of the Larix olgensis L. Henry areal in the Primorskii krai has been carried out. The main amount of chromosomes for larch as n = 12 (2n = 24) has been confirmed. Mixoploidy was observed in all studied populations. The difference of individuals from the larch areal based on the cell amount with a different level of ploidity has been found in the population of L. olgensis locus classicus and both L. sibirica and L. gmelinii, which is probably a consequence of their hybrid nature.