(Correct first paragraph to say Brazil is offering a new 30-year bond, not a 20-year bond) SAO PAULO/BRASILIA, July 23 (Reuters) - Brazil's Treasury is offering on Wednesday a new 30-year global bond and buying back as many as eight shorter-dated issues, in a bid to take advantage of growing appetite for Brazilian assets and improve the country's dollar-denominated yield curve.

The Treasury said in a statement it has mandated banks to sell a new global bond maturing in January 2045 and to buy back issues maturing from 2024 to 2041.

Bank of America Merrill Lynch, Deutsche Bank and Itau are handling the operation, which is expected to price later on Wednesday, a source with direct knowledge of the deal said. Initial price guidance for the sale of the new 2045 bond is around 200 basis points over comparable U.S. Treasuries, the source added.

Currently there are a combined $11.9 billion in notes maturing in 2024, 2025, 2027, 2030, 2034, 2037 and 2041.

Bond Maturity Coupon Outstanding amount (pct) USD Global 2024 April 15, 2024 8.875 1,145,684,000.00 Global 2024 B April 15, 2024 8.875 95,037,000.00 Global 2025 Feb 4, 2025 8.750 1,043,516,000.00 Global 2027 May 15, 2027 10.125 1,396,058,000.00 Global 2030 March 6, 2030 12.250 466,450,000.00 Global 2034 Jan 20, 2034 8.250 1,956,412,000.00 Global 2037 Jan 20, 2037 7.125 2,870,304,000.00 Global 2041 Jan 7, 2041 5.625 2,925,000,000.00 (Reporting by Guillermo Parra-Bernal and Luciana Otoni, writing by Walter Brandimarte; Editing by W Simon and Paul Simao)