Cryptolepis

A new approach to indoloquinohne alkaloids from Cryptolepis sanguino-lenta has been reported based on the cyclization of an o-substituted vinyl isocyanate 244 imder microwave irradiation and further additional cyclization based on an Aza-Wittig reaction carried out in the presence of microwaves [159]. The apphcation of this synthetic scheme to the synthesis of Cryptotackienine 247 is reported in Scheme 91. 

Homocryptolepinone 426 (Figure 10) was isolated from the extracts of the indigenous Ghanaian medicinal plant Cryptolepis sanguinolenta (1995JHC1631), as well as the alkaloid cryptoheptine 427 that was identified in other related... 

Cryptolepis species, extracts of which are used in traditional medicine in Central and West Africa (1996TL4283, 2000JNP643). 

Few alkaloids have been found in this relatively large family. Those in Cryptolepis, Cynanchum, Pergularia, Tylophora, and Vm-cetoxicum have been characterized, some have been synthesized, others have yet to be isolated in pure form. 

Cryptolepine [root] Cryptolepis sanguinolenta, DNA (intercalation) (TOPII)... 

Cryptolepine (Ranunculaceae) Cryptolepis sanguinolenta, TOPII (formation of cleavable... 

There were a several additional studies of members of the indoloquinoline family of alkaloids isolated from Cryptolepis sanguinolenta reported that utilized 3 mm micro-NMR probe capabilities reported in 1995. The elucidation of the structure of quindolinone (16) was reported next and also utilized 3 mm micro-probe technology for the acquisition of a HMQC spectrum on an 800 pg sample of the... 

Cryptospirolepinone is the most complex member of the cryptolepis family of alkaloids, constituted as a spiro nonacyclic molecule 5 [85]. The molecule also required the acquisition of multiple long-range H- N spectra to assign all of the N resonances in the structure. Data were acquired with optimizations of 10,6,4, and 2.5 Hz. A single correlation from H-13 to the N-3 resonance was observed only in the 2.5 Hz optimized spectrum, while correlations were readily observable to the other three nitrogen resonance in the structure [86]. 

Venkateswara, R., Narendra, N., Viswamitra, M.A. and Vaidyanathan C.S. (1989) Cryptosin, a cardenolide from the leaves of Cryptolepis buchanani. Phytochemistry, 28, 1203-5. 

The root of the plant Cryptolepis sanguinolenta (Lindl.) Schlt (Periplocaceae) is used in traditional African medicine to treat a variety of diseases including malaria, jaundice, hepatitis, urinary tract infections, hypertension, inflammatory conditions and stomach ache. Extracts of the roots are also used as a tonic often taken daily for years without evidence of toxicity. Various studies indicate that the crude extracts as well as the isolated alkaloidal constituents of the plant possess a number of interesting pharmacological properties. The focus of this overview is to highlight the potential of Cryptolepis sanguinolenta in modem health care. 

Tackie, A., Schiff, P., Sharaf, M. Antimalarial alkaloids from Cryptolepis sanguinolenta. WO9418203. PCT Int. Appl. (1994). 

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