Synthesis And Biological Activities Of Several Series Derivatives Form Progesterone

There has been an extensive research towards the rational modification of steroidmolecules probably because of the various advantages associated with steroidal derivatives. Ithas been proved by different ring modification studies of steroidal molecules involving the A-and D-ring whereby incorporation of heteroatom （N, O or S） has been reported to show awide range of different biological activities such as anti-inflammatory, hypocholesterolemicand diuretic activities. Progesterone is one of the most important hormones of the steroidalpregnane series and plays important roles for the maintenance of sexual cycle and pregnancyand can be regarded as a hormonal balancer, particularly of estrogens. The structure ofprogesterone is pregn-4-ene-3,20-dione and a large number of studies revealed thatderivatives of progesterone have varied biological activities, such as remarkableneuroprotection following traumatic brain injury as well as potential antimicrobial andanti-inflammatory functions.Due to the importance of progesterone to the human body and its inherent steroidalstructure, based on previous work on rational modification of steroid molecules, wesynthesized a few series compounds derived from progesterone （The synthetic route are listedin figure1）. Eighty-one compounds were obtained, of which seventy-one compounds werethe first time to report. The results are concluded as follow:1.Pregn-1,4-diene-3,20-dione2was directly obtained through1-dehydrogenation ofprogesterone1. On the other hand, introduction of a chlorine atom at C-4of1and then1-dehydrogenation gave another intermediate,4-chloro-pregn-diene-3,20-dione5. Then, aldolcondensation reactions of the intermediates2and5with various benzaldehydes6a-h,afforded the corresponding target benzylidene derivatives7a-h and8a-h. These compoundswere evaluated for their cytotoxic activty against brine shrimp （Artemia salina） and murineLewis lung carcinoma cells （LLC）.It was found that these compounds7a-hexhibited similar cytotoxicity against brineshrimp, with LC50values of17.7-28.3μg/mL.In contrast, compounds8a-h, which contained achlorine atom at C-4position and possessed the same counterpart of aromatic aldehydes as7a-h, caused a loss of activity (LC₅₀>50μg/mL). From the cytotoxicity results tested by the MTT assay, we found that the benzylidene derivatives7a-h and8a-h showed someinhibitive effects （inhibition rate of5.96%to66.18%） to LLC cells at concentrations of30μg/mL, of which7f and8a displayed a weak cytotoxic activity （66.18%and51.12%,respectively） at this concentration. 2.4′-Nitro of benzylidene derivative7g was reduced to afford4′-amino and obtainedcompound9. Then,9underwent aminoacylation with acyl chloride10a-v to provide thetarget4′-acylamino-modified benzylidene derivatives11a-v. These compounds wereevaluated for their cytotoxic activty against brine shrimp （Artemia salina） and two humancancer cell lines i （HeLa and MCF-7）. It was found that after4′-nitro compound7g was reducted to4′-amino derivative9, thecorresponding cytotoxicity against brine shrimp was enhanced with the LC50value changedfrom27.6μg/mL to15.9μg/mL. In contrast, all of the4′-acylaminobenzylidene derivatives11a-v displayed weaker or even disappeared such activity. From the cytotoxicity results testedby the MTT assay, we found that the benzylidene derivatives11a-v at concentrations of30μg/mL showed some inhibitive effects and and the variation of acylamino groups at4′-position on the benzene ring were sensitive to the cytotoxic activity response. Theinhibition rate of two cells （HeLa and MCF-7） were ranged form21.83%to66.18%and1.19%to64.00%, respectively, of which, compound11f exhibited the strongest inhibitoryeffects on both cell lines （58.13%of HeLa and64.00%of MCF-7） at at this concentration.3.Through cyclisation reaction with hydrazine hydrate in acetic acid solution, substrate7a-h and8a-h further offered C-17pyrazolinyl derivatives12a-h and13a-h. Thesecompounds were evaluated for their cytotoxic activty against brine shrimp （Artemia salina）and three human cancer cell lines （NCI-H460, HeLa and HepG2）. The effects on cell cycledistribution of HeLa cells which treated with different concentrations of the most potentpyrazolinyl compound13b （10,20or40μg/mL） were evaluated by flow cytometry.Moreover, we measured the insecticidal activities against the4^th instar larvae （Mythimnaseparata） of13a-h by the leaf disc method.The results indicated that compounds13a-h significantly inhibited the growth of thebrine shrimp larvae (LC₅₀=4.99-27.33μg/mL), of which, compound13a was the most activeone ((LC₅₀=4.99μg/mL). On the other hand, compounds12a-h, which lacked a chlorineatom at C-4position and possessed the same counterpart of aromatic aldehydes as13a-h,caused a decrease in activity (LC₅₀=18.94-44.89μg/mL). From the cytotoxicity resultstested by the MTT assay, we found that the pyrazolinyl13a-e exhibited moderate in vitrocytotoxic activity to the three human cancer cell lines （NCI-H460, HeLa and HepG2）,showing IC50values ranging from10.3to26.6μg/mL. The HeLa cell cycle distributionanalysis indicated that13b arrested the cell population in the S phase and its concentrationsaffected the DNA percentage of S phase. This results imply that the cytotoxic effect of13bcould be preceded by the accumulation of cells in the S phase.It was also found that13a-h showed potent insecticidal activity against the4thinstarlarvae of M. separata. Notably, compounds7a, with a none substituent aromatic ring, wasfound to exert the most potent insecticidal activity (LD₅₀=296.65μg/g), comparable to thatof the positive control celangulatin V (LD₅₀=260.05μg/g).4.4-Hydroxyprogesterone （14） was obtained by introduction of a hydroxy at C-4ofprogesterone1.Then,14reacted with acyl chloride15a-p to offer4-acyloxyprogesterone derivatives16a-p. Their relative bioactivity are under investigation.5.In additional, an attempt to synthesize the thiazole derivatives from progesterone wasdone.