Mackinlaya

The alkaloid vasicine was first isolated from Adhatoda vasica in 1925 but the structure (996) was elucidated only after a great amount of work, culminating in two independent syntheses in 1935 (B-53MI21301). It was made subsequently by a simple route from 2-aminobenzaldehyde and 4-amino-2-hydroxybutyraldehyde (994) followed by dehydration of the tricyclic intermediate (995) (60TL(25)44>. Vasicine has bronchodilatory activity of a low order. Two related unnamed alkaloids (997) and (998) were obtained in 1965 from members of the Araliaceae family, viz. Mackinlaya subulata and M. macrosciadia both had been synthesized earlier (66AJC151). 

Although discussion of the chemistry and biochemistry of pyridylpiperi-dines, bipiperidines, and related reduced bipyridines is outside the scope of a review on bipyridines, it is necessary for the understanding of subsequent sections of this review to record the structures of reduced 2,3 -bipyridines that occur naturally. Several compounds of this type are important alkaloids isolated from several plant species, notably. Anabasis, Duboisia, Mackinlaya, Marsdenia, Nicotiana, and Priesteya. Anabasine (also known as neonicotinel has structure 12 (R = H), and is insecticidal. The closely related structures 1-methylanabasine (12 R = anatabine (13 R = its... 

Several unnamed alkaloids have been recorded in some ten genera of the family. Quinazolines have been characterized from the genus Mackinlaya the known alkaloidal M. schlechieri was also found positive in this study. 

From Mackinlaya subulata and M. macrosciadia the tetrahydropyr-ido[2,l-6]quinazoline 202 and its 11-oxo derivative 203 were ob-tained. - - ... 

The genus Mackinlaya (Arali tce ie) on the other hand yielded quinazolines of a type not previously encountered, such as 37 52], accompanied by a base (38) with a macro heterocyclic ring that appears to be biosynthetically related to the quinazoline types 53]. 

Mackinlaya macrosciadea F. Muell. and M. klossii Philipson (Araliaceae) (X, 572)... 

Leaves and stems of the two Mackinlaya species, M. macrosciadia (F. Muell.)... 

Deoxyvasicinone (33) C11H10N2O 110-ni Unaria sp. (112) Mackinlaya macrosciadia (F. Muell.) F. Muell. (Ill) Peganum harmala L. (107-109) P. nigellastrum (110) Adhatoda vasica Nees (152)... 

Fitzgerald, Johns et al. (67, 99) have isolated two alkaloids (61) and (62) from the leaves and stems of Mackinlaya subulata and M. macrosciadia. Both were readily identified by a combination of physical and chemical methods, and the structures were confirmed by direct comparison with synthetic samples. 

Johns, S. R., and J. A. Lamberton Alkaloids of Mackinlaya Species (Family Araliaceae). J. Chem. Soc. Chem. Commun. 1965, 267. 

Pyrroloquinazoline alkaloids have been reported from the Acanthaceae (Adhatoda vasica, Anisotes), Araliaceae Mackinlaya), Fabaceae (Galega), Malvaceae Sida), Scro-phulariaceae (Linaria), and Zygophyllaceae Peganum) (Johne, 1986). 

Deoxyvasicine III Adhotoda vasica (Acanthaceae) [18], Mackinlaya macrosciadea (Araliaceae) [19], Nitraria schoberi (Zygophyllaceae) [35], Peganum harmala (Zygophyllaceae) [40], P. multisectum [32], P. nigellastrum [32]... 

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