6 documents found, page 1 of 1
An Exemestane Derivative, Oxymestane-D1, as a New Multi-Target Steroidal Aromat...
Amaral, Cristina; Correia-da-Silva, Georgina; Almeida, Cristina Ferreira; Valente, Maria João; Varela, Carla; Tavares-da-Silva, ElisiarioAround 70-85% of all breast cancer (BC) cases are estrogen receptor-positive (ER+). The third generation of aromatase inhibitors (AIs) is the first-line treatment option for these tumors. Despite their therapeutic success, they induce several side effects and resistance, which limits their efficacy. Thus, it is crucial to search for novel, safe and more effective anti-cancer molecules. Currently, multi-target d...
Insights into the Synthesis of Steroidal A-Ring Olefins
Varela, Carla M.; Roleira, Fernanda M. F.; Costa, Saul C. P.; Tinto, Alexandra S. C. T.; Martins, Ana I. O. S.; Carvalho, Rui A.; Teixeira, Natércia A.one (5), from the D1-3-keto enone, (5a,17b)-3-oxo-5-androst-1-en-17-yl acetate (1), through a strategy involving the reaction of D1-3-hydroxy allylic alcohol, 3b-hydroxy-5a-androst-1-en-17b-yl acetate (2), with SOCl2 , was revisited in order to prepare and biologically evaluate 5 as aromatase inhibitor for breast cancer treatment. Surprisingly, the followed strategy also afforded the isomeric D2-olefin 6 as a b...
New steroidal 17b-carboxy derivatives present anti-5a-reductase activity and an...
Amaral, Cristina; Varela, Carla; Correia-da-Silva, Georgina; Silva, Elisário Tavares da; Carvalho, R. A.; Costa, Saul C. P.; Cunha, Sara C.The androgens testosterone (T) and dihydrotestosterone (DHT), besides playing an important role in prostate development and growth, are also responsible for the development and progression of benign prostate hyperplasia (BPH) and prostate cancer. Therefore, the actions of these hormones can be antagonized by preventing the irreversible conversion of T into DHT by inhibiting 5a-reductase (5a-R). This has been a ...
New steroidal aromatase inhibitors: suppression of estrogen-dependent breast ca...
Cepa, Margarida; Correia-da-Silva, Georgina; Silva, Elisiário da; Roleira, Fernanda M. F.; Borges, Margarida; Teixeira, Natércia A. A.Background: Aromatase, the cytochrome P-450 enzyme (CYP19) responsible for estrogen biosynthesis, is an important target for the treatment of estrogen-dependent breast cancer. In fact, the use of synthetic aromatase inhibitors (AI), which induce suppression of estrogen synthesis, has shown to be an effective alternative to the classical tamoxifen for the treatment of postmenopausal patients with ER-positive bre...
Synthesis and biochemical studies of 17-substituted androst-3-enes and 3,4-epox...
Cepa, Margarida M. D. S.; Silva, Elisiário J. Tavares da; Correia-da-Silva, Georgina; Roleira, Fernanda M. F.; Teixeira, Natércia A. A.http://www.sciencedirect.com/science/article/B6TC9-4T0WJXG-2/2/58305e64e3c068f352293a693f168db2
Structure−Activity Relationships of New A,D-Ring Modified Steroids as Aromatase...
Cepa, Margarida M. D. S.; Silva, Elisiário J. Tavares da; Correia-da-Silva, Georgina; Roleira, Fernanda M. F.; Teixeira, Natércia A. A.Inhibition of aromatase is an efficient approach for the prevention and treatment of breast cancer. New A,D-ring modified steroid analogues of formestane and testolactone were designed and synthesized and their biochemical activity was investigated in vitro in an attempt to find new aromatase inhibitors and to gain insight into their structure−activity relationships (SAR). All compounds tested were less active ...