Abstract: The ability to synthesize capped RNA transcripts in vitro has been of considerable value in a variety of applications. However, one-third to one-half of the caps have, until now, been incorporated in the reverse orientation. Such reverse caps impair the translation of in vitro-synthesized mRNAs. Novel cap analogues, such as P1-3?-deoxy-7-methylguanosine-5? P3-guanosine-5? triphosphate and P1-3?-O,7-dimethylguanosine-5? P3-guanosine-5? triphosphate, have been designed that are incapable of being incorporated into RNA in the reverse orientation. Transcripts produced with SP6 polymerase using “anti-reverse” cap analogues were of the predicted length. Analysis of the transcripts indicated that reverse caps were not formed. The in vitro translational efficiency of transcripts with the novel “anti-reverse” cap analogues was significantly higher than that of transcripts formed with conventional caps.

Abstract: The ability to synthesize capped RNA transcripts in vitro has been of considerable value in a variety of applications. However, one-third to one-half of the caps have, until now, been incorporated in the reverse orientation. Such reverse caps impair the translation of in vitro-synthesized mRNAs. Novel cap analogues, such as P1-3?-deoxy-7-methylguanosine-5?P3-guanosine-5?triphosphate and P1-3?-O,7-dimethylguanosine-5?P3-guanosine-5?triphosphate, have been designed that are incapable of being incorporated into RNA in the reverse orientation. Transcripts produced with SP6 polymerase using “anti-reverse” cap analogues were of the predicted length. Analysis of the transcripts indicated that reverse caps were not formed. The in vitro translational efficiency of transcripts with the novel “anti-reverse” cap analogues was significantly higher than that of transcripts formed with conventional caps.

Abstract: The ability to synthesize capped RNA transcripts in vitro has been of considerable value in a variety of applications. However, one-third to one-half of the caps have, until now, been incorporated in the reverse orientation. Such reverse caps impair the translation of in vitro-synthesized mRNAs. Novel cap analogues, such as P1-3′-deoxy-7-methylguanosine-5′P3-guanosine-5′triphosphate and P1-3′-O,7-dimethylguanosine-5′P3-guanosine-5′triphosphate, have been designed that are incapable of being incorporated into RNA in the reverse orientation. Transcripts produced with SP6 polymerase using “anti-reverse” cap analogues were of the predicted length. Analysis of the transcripts indicated that reverse caps were not formed. The in vitro translational efficiency of transcripts with the novel “anti-reverse” cap analogues was significantly higher than that of transcripts formed with conventional caps.

Abstract: Pyridyl-alanyl decapeptides have been effectively synthesized and found to have antiovulatory activity. The exemplary [N-Ac-D-2-Nal.sup.1,pCl-D-Phe.sup.2, D-3-Pal.sup.3,D-Arg.sup.6,D-Ala.sup.10 ]-LHRH has very high potency to inhibit ovulation, both parenterally and orally. Also, this exemplary pyridyl-alanyl-decapeptide showed an unexpected prolonged duration of antiovulatory activity. Such pyridyl-alanyl-decapeptides are useful to control reproduction.