
Molecular model of penicillin by Dorothy M Crowfoot Hodgkin, England, 1945
1945
1945
1949
1945-1948
1949
1947
circa 1942
1945
1947
2000-100 BCE
1948
1946
1945
1945
1943
1949
1948
1948
1955; 1830
1944
1938 and 1951
1943
1946-1948
1944-1945
1946
1942
1948
1946
1948
1942
1946
1946
1942
1948
1948
1949
1801-1892 (prepared); 1946 (element replaced)
1948
4000-2001 BCE
1942-1945
1942-1945
1839 (original); circa 1988 (replica)
1947
1990-96
1944
circa 1947
1943-1945
1947
circa 1945
1949
1945-1946