Tecoma stans

Costantino L, Raimondi L, Pirisino R, Brunetti T, Pessotto P, Giannessi F, Lins AP, Barlocco D, Antohni L, El-Abady SA. (2003) Isolation and pharmacological activities of the Tecoma stans alkaloids. 11 Farmaco 58 781-785. 

DiOH-6,4 -diOMe CiyHieOe 316 Tecoma stans Bignoniaceae Flower 28... 

A stereoselective synthesis of ( )-tecomanine (16), an alkaloid of Tecoma stans Juss., has been achieved and is outlined in Scheme 4.22... 

Gnaphalium semiamplexicaule (gordolobo) Tecoma stans (tronadora)... 

Tecoma stans,93 have been shown to catalyze the condensation of o-aminophenol to 2-amino-3i/-phenoxazin-3-one (52, R = H) to which the name questiomycin A has been given by Anzai et al.9i This compound has been isolated also from Streptomyces fungicidicus,9 and, along with 2-acetylamino-3i/-phenoxazin-3-one (52, R = COCH3), from members of the actinomycete genus Waksmania.96... 

A new monoterpene alkaloid, kinabalurine G (330) has been obtained from the leaf extract of Kopsia dasyrachis in addition to 11 known alkaloids and the novel pentacyclic indole, danuphylline vide infra) [223]. Analysis of the spectral data allowed assignment of the gross structure as well as determination of the stereochemistry at the various centers. Kinabalurine G (330) is the AZ-oxide of 9-hydroxy-S-skytanthine, which is unknown, although a 9-hydroxy-skytanthine of unknown stereochemistry has been previously reported from Tecoma stans [224]. 

Reduced analogues of venoterpine include tecomanine (95), an alkaloid from Tecoma stans. The structure of this base is known from X-ray studies and a stereoselective synthesis of its racemic modification has been published (T. Imanishi,... 

Tecomine was originally isolated from Tecoma stans in 1959 by Ham-mouda and Motawi (90) and subsequently by Jones and co-workers (45,91), who named the alkaloid tecomanine. Direct comparison of the alkaloids and their picrates established their identity (92). Therefore the former name, tecomine, should take precedence. However, current nomenclature in usage for the alkaloid and for its derivatives has favored the name tecomanine, and this name will be used here. 

The leaves of Tecoma stans (Bignoniaceae) were studied previously (1) because of their reputed antidiabetic properties, which appear to have been traced to the monoterpene alkaloid fraction. Further studies of this plant by Lins and D arc Felicio (42) have now revealed the presence of two new alkaloids, 7-hydroxy-5,6-dehydroskytanthine (58) and 4-hydroxy-tecoman-ine (59), in the fruits of T. stans. In addition, two known alkaloids, 5/3-hydroxy-skytanthine (44) and tecomanine (55) were obtained. H and 13C NMR data for these known alkaloids were reported for the first time. 

A detailed study of the mass spectra of seven of the main alkaloids isolated from Tecoma stans has been described (238). As a result, the important fragmentation pathways for these alkaloids can be discussed. S-Skytanthine (33), 5/3-hydroxyskytanthine (44), 5,6-dehydroskytanthine (123), S-iV-normethylskytanthine (32), tecostanine (45), tecomanine (55),... 

Surprisingly few studies have been carried out of the formation of monoterpene alkaloids in plant tissue culture. Indeed the only work published appears to be that by Dohnal (89,243) from over 20 years ago. Using Tecoma stans cultures grown on media supplemented with mevalonic acid, lysine, or quinolinic acid, alkaloid production was very limited or nonexis-... 

Monoterpenoid Alkaloids.—In accord with previous studies on the biosynthesis of the monoterpenoid alkaloids it has been found that mevalonate is incorporated into (5-skytanthine (233), tecostanine (234), tecomanine (235), and boschniakine (236) in Tecoma stans. 

Hammouda Y and Khalafallah N, Stability of tecomine, the major antidiabetic factor of Tecoma stans (Juss.) f. Bignoniaceae, /. Pharm. Sci., 60,1142-1145 (1971). NB The free base was titrated with standard NaOH to the pH of half-neutralization, which was taken as the pJCa value, and reported as pK, = 6.8, thus assuming that the result was valid at 25 °C. 

Tariric acid, 13, 53 Tay-Sachs disease, 544 TBHQ (tert-butylhydroquinone), 221 Tea leaves, 459 Tea seed oil, 93 Tecoma stans, 5 Teichoic acid, 46,47,158 Temperature dependence, dielectric constant, 357 Tempo, 422... 

The biosynthesis of simple monoterpenes has not been studied extensively. Acetate, mevalonate, and geranylpyro-phosphate are incorporated into actinidine. However, neither loganin (2) nor actinidine (8) serves as a precursor for p-skytanthine (9) or its derivatives in Tecoma stans (Bigno-niaceae) (Fig. 36.2). These compounds appear to be derived from an intermediate preceding loganin in the biosynthetic pathway. 

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