The alkaloid content (colchicine, 2-demethydemecolcine, 3-demethyldemecolcine, N-formyl-N-deacetylcol-chicine, cornigerine, demecolcine) of corms, leaves and flowers of Merendera kurdica and of corms of M. manissadjianii and M. sobolifera was determined by HPLC. In addition to these compounds, all corms contained the flavone luteolin, and benzoic, 2-hydroxy-6-methoxybenzoic and vanillic acids. A new homoaporphine alkaloid baytopine was isolated from the leaves and flowers of M. kurdica. The UV and CD spectra of five homoaporphine alkaloids, baytopine, bechuanine, CC-24, kreysigine, and O-methylkreysigine, measured in ethanol and sodium ethoxide show marked differences which are discussed.

1. Biotransformation of 1,4-diethenylbenzene (1) in rat was studied. Six urinary metabolites, namely, N-acetyl-S-[2-(4-ethenylphenyl)-2-hydroxyethyl]-L-cysteine (3), N-acetyl-S-[1-(4-ethenylphenyl)-2-hydroxyethyl]-L-cysteine (4), N-acetyl-S-[1-(4-formylphenyl)-2-hydroxyethyl]-L-cysteine (5), 1-(4-ethenylphenyl)ethane-1,2-diol (6), 4-ethenylbenzoic acid (9) and 4-ethenylbenzoyl-glycine (12) were isolated and identified by n.m.r. and mass spectrometry. 2. G.l.c.-mass spectral analysis of the methylated urine extract allowed the identification of four other metabolites, as 4-ethenylphenylacetic acid (11), 4-ethenylphenylacetylglycine (13), 4-ethenylmandelic acid (7), and 4-ethenylphenylglyoxylic acid (8). 3. The structures of the identified metabolites indicate that the main reactive intermediate in the metabolism of 1 is 4-ethenylphenyloxirane (2). The first step in the biotransformation of 1, formation of an oxirane, is very similar to the metabolic activation of styrene. However, subsequent steps lead not only to analogues of styrene metabolites but also to oxidation of the second ethenyl group leading to compound(s) which may contribute to the toxicity of 1, e.g. to the aldehyde 5. 4. Rats dosed with a single i.p. dose of 1 excreted nearly 5.6% of the dose as the glycine conjugate 12, irrespective of the dose. 5. In contrast, the total thioether fraction decreased significantly with increasing dose, being 23 +/- 3, 17 +/- 5 and 12 +/- 1% of dose at 100, 200 and 300 mg/kg, respectively (mean +/- SD).

The synthesis, TLC data and spectral characteristics of mercapturic acid methyl esters derived from five industrially important methacrylates and methacrylamide are described.

AbstractAcrylnitriloxid (I) reagiert mit L‐Cysteinmethylester‐hydrochlorid (II) über diskutierte Zwischenstufen zu den Heterocyclen (III) und (IV).

AbstractDas aus dem Bis‐hydrazon (I) und dem Diketon (II) bzw. durch Eigenkondensation von (IV) zugängliche Tetraaza‐Derivat (III) geht direkt in das bicyclische Betain (V) über, das bei der Photolyse in Abhängigkeit von der Wellenlänge zu den Umlagerungs‐ 35 produkten (VI)‐(X) führt.

The loss of histidine and the formation of additional by-products during the purification and storage of [14C(U)]-L-histidine preparations on chromatographic carriers was followed. The product formed mainly on chromatographic paper was identified as the condensation product of histidine with formaldehyde; on thin layer of silica gel mainly degradation products of histidine were obtained. Possibilities to decrease the formation of these undesirable by-products were discussed.

AbstractThe mass spectra of four of the six 1,4‐dihydroxy‐ Δ6,7‐octalins are reported. The spectra differ considerably, depending on the configuration of the hydroxyl groups. The relative amounts of 1‐3,1‐4, transannular 1‐3 and hydroxyl‐hydroxyl elimination of water from the molecular ions were determined by using specificaliy labelled compounds. Effects of configuration and conformation are discussed.

AbstractThe Schiff bases of benzaldehyde and aliphatic amines form immonium ions on electron‐impact, which rearrange and eliminate hydrogen cyanide in a different way than the corresponding derivatives of pyridine‐2‐aldehyde. The presence of at least one hydrogen on the α‐carbon atom in the amine moiety is a necessary condition for this rearrangement. A mechanism is suggested for this process.

Durch Umsetzung von 1,4-Diphenyl-2,6-dioxopiperazin mit Benzolsulfonyl- oder Benzolsulfenylchlorid in Pyridin wurde die Verbindung VI mit mesoionischer Struktur dargestellt. Diese Verbindung liefert durch dipolare Cycloaddition von Maleinanhydrid bzw. Formaldehyd die Addukte VII und VIII. Die Reaktionen der Verbindung VI führen je nach der Natur des Reagens entweder zu Produkten, in denen das Piperarinskelett erhalten bleibt (saure Hydrolyse, Oxydation, Reduktion). oder zu Derivaten von Maleinimin-Typus (Aminolyse). In einigen Fällen können Produkte von beiderlei Typus gebildet werden (Desulfurierung mit Raney-Ni). By transformation of 1,4-diphenyl-2,6-dioxopiperazme with benzenesulphonyl or benzenesulphenyl chloride m pyridine, compound VI with mesoionic structure was prepared. This compound yields by dipolar cycloaddition of maleic anhydride or formaldehyde adducts VII and VIII. According to the character of the reagent, the reactions of compound VI lead either to products which preserve their piperazine ring (acid hydrolysis, oxidation, reduction), or to derivatives of the maleic imide type (aminolysis). In some cases, products of both types are formed (desulphurization with Raney nickel).

AbstractDurch Umsetzung des Piperazins (I) mit den Chloriden (II) wird die mesoionische Verbindung (III) (9 bzw. 28% Ausbeute) erhalten, wobei die angegebene Struktur nur eine der 6 möglichen kanonischen Formeln darstellt.

The effects of biotic stresses on the contents of benzoxazinones (Bxs) were investigated in maize leaves. When the causal agent of southern corn leaf blight, Bipolaris maydis, was inoculated on the third leaf, the amount of 2-hydroxy-4,7-dimethoxy-1,4-benzoxazin-3-one glucoside (HDMBOA-Glc) increased, reaching a maximum level 48 h after inoculation. The inoculation of weakly pathogenic Curvularia lunata and non-pathogenic Alternaria alternata also resulted in accumulation of HDMBOA-Glc, and filtrates of the cultures of B. maydis, C. lunata and A. alternata also showed the accumulation of elicitor-active compounds by the fungi. Furthermore the infection of B. maydis induced formation of dark brown lesions, where most abundant Bx-related compound was 6-methoxy-2-benzoxazolinone (MBOA). The later is formed by degradation of DIMBOA and HDMBOA, whereas HDMBOA-Glc was most abundant in the surrounding green tissues. Among the Bx-related compounds, MBOA exhibited the strongest inhibition of the germination of the conidia and of the growth of germ tubes of B. maydis, C. lunata and A. alternata. In addition to fungal infection, the feeding by rice armyworm larvae resulted in HDMBOA-Glc accumulation. These findings are discussed in relation to the possible ecological relevance of the conversion of DIMBOA-Glc into HDMBOA-Glc.

IONIZATION by electron impact of toluene1,2 and some other compounds containing the benzyl group3 leads to the formation of tropylium ions, as Meyerson and Rylander have shown by isotopic labelling1 and comparison of the energy data as well as of the mass spectra2 of toluene and cycloheptatriene. The discovery of this rearrangement is of importance for the verification of basic conceptions on factors determining ion fragmentation (cf. ref. 4). In this connexion we should like to direct attention to the mass spectrum of spiro-(2,4)-cycloheptadiene-(1,3).