Co-founder and Non-Executive Chairman of Chariot Oil and Gas, an Africa-focused exploration company, Adonis Pouroulis, has scooped up 100,000 shares in the firm.He made the purchase on Tuesday, the same day the company admitted that the Tapir South well (1811/5-1), offhore Namibia, failed to find commercial hydrocarbons, and will now be plugged and abandoned.Pouroulis purchased the shares at 74.95p each for a total of £74,950. His colleage Larry Bottomley, a Non-Executive Director, also bought up two rounds of shares, one of which was on behlaf of his wife. The transactions consisted of 20,104 at 81.00p for a total of £16,284 and 20,289 at 80.00p at £16,231, respectively. The purchases were announced on Wednesday, the same day broker UBS slashed its target price on the stock from 340p to 215p, but said: "Namibia is fast becoming an exploration hot spot, driven by large, cheap acreage positions, and good fiscal terms, with a government looking to increase foreign investment. "Chariot has indentified a portfolio of prospects and leads with a total estimated mean-unrisked resource potential of over 20bn barrels of oil in its offshore Namibian licences. "The company recently spudded the first of two wells this year at Tapir South, and will drill the giant Nimrod prospect later in the year."UBS also maintained its buy rating on the stock. Top Director BuysChariot Oil & Gas Ltd. (CHAR) Director name: Mr Adonis PouroulisAmount purchased: 100,000 @ 74.95p Value: £74,950Biotech Growth Trust (The) (BIOG) Director name: Mr Andrew Joy Amount purchased: 25,000 @ 249.00p Value: £62,250Exillon Energy (EXI) Director name: Mr David HerbertAmount purchased: 42,750 @ 115.35p Value: £49,312Vitec Group (VTC) Director name: Mr Nigel MooreAmount purchased: 5,000 @ 648.50p Value: £32,425Ladbrokes (LAD) Director name: Mr Richard AmesAmount purchased: 10,000 @ 168.47p Value: £16,847Chariot Oil & Gas Ltd. (CHAR) Director name: Mr Larry BottomleyAmount purchased: 20,104 @ 81.00p Value: £16,284Chariot Oil & Gas Ltd. (CHAR) Director name: Mr Larry BottomleyAmount purchased: 20,289 @ 80.00p Value: £16,231Top Director SellsAnglogold Ashanti Ltd. (AGD) Director name: Mr Mark CutifaniAmount sold: 34,601 @ 2,012.39p Value: £696,307Anglogold Ashanti Ltd. (AGD) Director name: Mr S (Venkat) VenkatakrishnanAmount sold: 28,218 @ 2,012.39p Value: £567,856Archipelago Resources (AR.) Director name: Mr Jeremy Ayre Amount sold: 94,778 @ 58.00p Value: £54,971Archipelago Resources (AR.) Director name: Mr Jeremy Ayre Amount sold: 94,778 @ 58.00p Value: £54,971