Tylophora asthmatica

Furoquinoline Alkaloids.—Well-known furoquinoline alkaloids have been identified for the first time in twelve species of the Rutaceae (see the Table 2.5.8,9,11—13,15,16 on p an(j rare trimethoxydictamnine halfordinine (1 R1 = R2 = R3 = OMe) has been obtained from Araliopsis tabouensis2 and from Teclea verdoorniana.12 The isolation of y-fagarine and skimmianine from Tylophora asthmatica (Asclepiadaceae)14 and skimmianine from Datura stramonium (Solanaceae)4 is of considerable taxonomic interest. 

Phenanthroindolizidine Alkaloids.—The phenanthroindolizidine alkaloids, e.g. tylophorine (14) and tylophorinine (15), are assembled in Tylophora asthmatica from fragments derived from ornithine, phenylalanine, and tyrosine (cf. Vol. 8, p. 6 Vol. 9, p. 5). The last amino-acid is the source of ring B plus C-9 and C-10. It has now been shown that dopa is a better precursor than tyrosine for this fragment. Label from [2-14C]dopa was specifically incorporated into C-10 of (14) and (15).16... 

Tylophora asthmatica, Cynanchum vincetoxkum, Pergularia pallida, Vincetoxicum officinale (Asclepiadaceae), Ficus septica (Moraceae)... 

Tylophorinine Peryplaria pallida Tylophora asthmatica Tylophora flava Tylophora mollissima Tylophora cordifolia Tylophora atrofoUiculata Tylophora indica Tylophora hirsuta Asclepiadaceae [36] [26,28,29,32] [31] [32] [31] [39] [33]... 

Tylophorine.—As a result of current work,70 the biosynthesis illustrated in Scheme 23 has been proposed for tylophorine (104). The evidence came from incorporation experiments in Tylophora asthmatica plants with [2-1 phenylalanine and [2-14C]tyrosine respectively. The alkaloid from each feeding was degraded to establish the labelling pattern shown in (104). Thus, tyrosine and phenylalanine are incorporated by completely separate pathways, probably as a... 

Tylophora asthmatica Wight Lf + Rt Dysentery, asthma, coughs, incipient... 

Phenanthroindoiizidine Alkaloids.—Previous results establish that the phenacyl-pyrrolidines (19), (20), and (21) are important precursors for phenanthroindoiizidine alkaloids, e.g. tylophorinine (28), in Tylophora asthmatica. These results and a consideration of the oxygenation pattern of the T. asthmatica bases in relation to possible biosynthesis by phenol oxidative coupling, as well as the structure (22) for the alkaloid septicine, pointed to (26) as a key intermediate. 

In addition to quinine and related alkaloids see Chapter 34), other quinoline alkaloids occur in Tylophora asthmatica (Asclepiadaceae) see Chapter 30). Two quinoline alkaloids have been reported from Melochia (Sterculiaceae) (Specialist Periodic Reports 1978, 1979). An alkaloid isolated from Broussonetia (Moraceae), 4-formyl-8-hydroxyquinoline, may not be closely related to other quinoline alkaloids. An... 

Although unusual, these alkaloids also are known from unrelated plant families. For example, Tylophora asthmatica (Asclepiadaceae) contains y-fagarine (19) and skimmianine (15) (Etherington et al., 1977). Skimmianine also has been reported from Datura stramonium. 

Etherington, T., R. B. Herbert, and F. B. Jackson, Furoquino-line alkaloids from Tylophora asthmatica. Phytochemistry, 16, 1125-1126(1977). 

Minor alkaloid from the leaves of Tylophora asthmatica and from T. tanakae (Asclepiadaceae). Cryst. (CH2Cl2/MeOH). Mp 212-214° (198-203° dec.), [a ... 

An alkaloid, possibility identical with tylophorinidine, 7, which was isolated by Rao from Tylophora asthmatica 18) and from T. dalzellii 18), showed significant activity in murine leukemia (L-1210 system). 

The phenanthroindolizidine alkaloids, e.g. tylophorine (6.81), are formed in Tylophora asthmatica from a molecule each of tyrosine and phenylalanine (see Scheme 6.20), with ornithine apparently the... 

Rathnagiriswaran AN, Venkatachalam K. The chemical examination of Tylophora asthmatica and isolation of the alkaloids tylophorine and tylophorinine. Indian J. Med. Res. 1935 22(3) 433 1. 

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