
Alexander Tsigutkin
President
Alex Tsigutkin came to the United States from Mariupol, Ukraine in 1980. Alex has spent more than 30 years on Wall Street as a fintech entrepreneur with education as a software engineer from both Yeshiva University and New York University. He is the founder of AxiomSL and served as its CEO from 1991 to the merger with Calypso in 2021.
Alex is currently a member of the Board of Directors of Adenza. He lives on the Upper East Side with his wife Diana and three children, Jeremy, Ruben and Matthew. Alex is passionate about Torah studies, Yiddishkeit and heavily involved in Jewish causes throughout the world.
Brian Kaufman
Vice President
Originally from Austin, Texas, Brian Kaufman is a Managing Director in the Real Estate Group at Blackstone. Prior to Blackstone, Brian was the Managing Partner of The Kaufman Companies, a privately held hospitality investment, development and asset management group in the U.S. and Europe. He previously worked at Highgate Capital Investment as Senior Vice President of Acquisitions and Development and at Goldman Sachs & Co in the Real Estate Principal Investment Area. In March 2019, he was awarded the IHIF and ISHC Young Leader Award at the International Hotel Investment Forum in Berlin.
Brian moved to New York after receiving a B.S. from Cornell University, where he was two-time All-Ivy League and Captain of the Varsity baseball team. He serves on the Dean’s Advisory Board for the Cornell Nolan School and on the Board of Cornell Nolan’s Center for Real Estate and Finance. Brian is involved in various Jewish organizations and charities, including B’nai B’rith International, where his father, Charles Kaufman, served as the organization’s 32nd President.


Boris Tiomkin
treasurer
Boris grew up in Moscow before he immigrated to Israel in 1975. In 1978 he graduated from Technion and served in the Israel Defense Forces from 1978 to 1981. From there he worked for investment banks moving from Johannesburg, South Africa to his final destination of New York City in 1987. In 2001 he founded the hedge fund administration company AIS Fund Administration, which was acquired by US Bank Corp in 2012. Boris happily retired in 2014 and has remained a private investor.
He is currently a proud member of the board of United Hatzalah of Israel and active in various Jewish charities. He resides in the Upper East Side with his wife Tanya with whom he has 2 children and 6 grandchildren and his many interests include classical music, theater, traveling, golf and of course, fly fishing.
Brad Colman
Brad lives on the Upper East Side with his wife, Maeva.
They have three children, Noa (10), Joshua (7) and Asher (1). Brad has spent the last 17 years since graduating from NYU working in investment banking and private credit.
He is currently a Senior Managing Director and the Head of Healthcare at Blackstone Credit, where he focuses on originating, analyzing, executing and monitoring credit investments.


Oriel Eisenberg
Estee Friedman-Stefansky
Estee Friedman-Stefansky is the principal of general studies at Manhattan High School for Girls, where she has been teaching and leading since 2003. She teaches Modern Literature and Social Psychology to the juniors and seniors. Estee holds a B.A. in English from Lander College, M.A. in English from Brooklyn College, and is currently pursuing her doctorate in educational leadership with a focus on social justice from Fordham University.
Estee and her husband David, an investment banker, live on the Upper East Side with their four children, Ariella, Uri, Elianna and Lola.


Aaron Stern
Aaron Stern is a Managing Partner and the Chief Investment Officer of Converium Capital, a multi-strategy opportunistic investment manager with offices in Montreal and New York. Prior to founding the firm, Aaron was a Partner and Managing Director at Fir Tree Partners. Prior to Fir Tree, Aaron held investment roles at O.S.S. Capital Management and Millennium Management and began his career as an investment banking analyst in Credit Suisse’s Leveraged Finance and Restructuring groups. He earned his bachelor’s degree in Commerce, with a Major in Accounting from McGill University, where he is a Global Expert and guest lecturer. Outside of the office, Aaron and his wife Sharon dedicate their time to their two boys Max and Adam and to Jewish, educational and pediatric health causes in Montreal and New York.