Browsing by Author "Rizk, A. M. [عبد الفتاح محمد رزق]"

Now showing items 1-6 of 6

    • Constituents of catha edulis (alkaloids, triterpenoids and related substances and saponins) 

      Rizk, A. M. [عبد الفتاح محمد رزق]; Mobarak, Z. M.; El-Shihi, T. ( Qatar University , 1989 , Article)
      The study of the alkaloids of khat samples from Egypt and Yemen revealed qualitative and quantitative differences. Cathine and the dimer of cathinone occured in both samples, while norephedine was detected only in Yemen ...

    • Constituents of plants growing in qatar part xxvii: flavonoids Of cymbopogon parkeri 

      Rizk, A. M. [عبد الفتاح محمد رزق]; Hammouda, F. M.; Ismail, S. I.; Kamel, A. S.; Rimpler, H. ( Qatar University , 1995 , Article)
      The study of the flavonoids of Cymbopogon parkeri resulted the isolation and indentification of tricin and isoorientin. Three other flavonoids have been isolated and partially identified.

    • Constituents of plants growing in qatar x.* seasonal variations of the volatile oil of cymbopogon parkeri 

      Rizk, A. M. [عبد الفتاح محمد رزق]; Sandra, P.; Mashaly, M.; Heiba, H. I. ( Qatar University , 1985 , Article)
      The seasonal variation of the volatile oil of Cymbopogon parkeri Stapf. was studied. The oil content is higher during the hot dry season than during the humid hot season and the cold season. No qualitative differences among ...

    • Constituents of plants growing in qatar xxiii. Flavonoids of francoeuria crispa 

      Rizk, A. M. [عبد الفتاح محمد رزق]; Hammouda, F. M.; Ismail, S. I.; Hussiney, H. A. ( Qatar University , 1993 , Article)
      Investigation of the flavonoid constituents of Francoeuria crispa, resulted in the isolation and identification of four flavonoids: quercetin, qucrcetin-3-O-gIucoside, quercetin-7-0-glucoside and quercetin-3-methyl ether.

    • Pyrrolizidine alkaloids from heliotropium arbainense and h. Ovalifolium 

      Rizk, A. M. [عبد الفتاح محمد رزق]; Hammouda, F. M.; Hassan, N. M. ( Qatar University , 1991 , Article)
      Investigation of the pyrrolizidine alkaloids of Heliotropium arbainense resulted in the isolation and identification of heliotrine, europine and 7-angelylheliotrine. From H. ovalifolium three alkaloids were isolated: ...

    • Pyrrolizidine Alkaloids From Senecio Aegyptius L. 

      Rizk, A. M. [عبد الفتاح محمد رزق]; Hammouda, F. M.; Ismail, S. I.; Hassan, N. M. ( Qatar University , 1988 , Article)
      Investigation of the alkaloidal constituents of Senecio aegyptius L. resulted in the isolation and identification of senecionine, dehydrosenkirkine and probably an isomer of seneciphylline. TLC, HPLC and GLC showed the ...